The “impact artifact” can be noted when the catheter is struck by the walls or valves of the cardiac chambers buy generic prothiaden 75mg online. The operator also needs to be aware of an artificially elevated pressure caused by streaming or high velocity of the pressure wave when using an end-hole catheter buy generic prothiaden 75mg on-line, the “end-pressure artifact order prothiaden 75mg amex. This is done by placing the transducer at the level of the atria, which is approximately midchest, and if more than one transducer is used, all should be calibrated simultaneously. To address the risk of drifting, all transducers should be rebalanced immediately before any simultaneous recordings. Micromanometer Catheters Micromanometer catheters allow for superior pressure recording because they have the pressure transducer mounted at the tip (e. This eliminates the interposing fluid column and its damping effect as well as the 30- to 40-millisecond delay. The pressure waveform is less distorted and the whip (motion) artifact is greatly reduced. These high-fidelity catheters, although more expansive, have been used to assess the rate of rise in ventricular pressure (dP/dt), wall stress, rate of decay in ventricular pressure (−dP/dt), time constant of relaxation (τ), and ventricular pressure-volume relationships. Catheters with two transducers separated by a short distance allow for accurate determination of gradients within chambers (e. Some of the high-fidelity micromanometer systems allow for over-the-wire insertion and angiography. There are two basic elements in the interpretation of pressure waveforms in a two-dimensional scale: the individual absolute values (y dimension) and the contour of the aggregated values over time (x dimension). Accordingly, the lack of this pattern indicates an abnormal relaxation pattern of the ventricle (also known as diastolic dysfunction). The right atrial pressure waveform has three positive deflections or waves (a, c, and v) and two negative deflections or descents (x and y). It is followed by the x descent, which represents atrial relaxation and downward pulling of the tricuspid annulus as the right ventricle contracts. Atrial filling and compliance determine the height of the v wave, and under normal conditions, the v wave is smaller than the a wave. With subsequent opening of the tricuspid valve and emptying of the right atrium into the right ventricle, atrial pressure drops again: the y descent. Inhalation leads to a drop in intrathoracic and right atrial pressure, and exhalation has the opposite effect. While overall similar, the left atrial pressure is generally higher, with a higher v than a wave. This is not the case under circumstances of elevated pulmonary vascular resistance (hypoxemia, pulmonary embolism, chronic pulmonary hypertension). In general, “overwedging” of the balloon catheter leads to falsely low values, whereas “underwedging” leads to falsely high pressure readings. These two scenarios can be recognized by the pressure waveform lacking its desired atrial waveform configuration: noticeably flat with overwedging and appearing as a dampened pulmonary artery pressure tracing with underwedging (eFig. True wedge position of the catheter should always be confirmed by a blood sample documenting systemic oxygen saturation (normally near 100%). Duration of systole, isovolumic contraction, and relaxation are longer, and the ejection period is shorter in the left than in the right ventricle. In the early, rapid filling phase of diastole, ventricular pressure initially drops quickly and then increases again, reaching a plateau. This plateau is extended over the slow filling phase but ended by a slow rise due to atrial contraction. The three key elements of the pressure waveform in the great vessels are the systolic wave (the ejection of the stroke volume through the open semilunar valves), the incisura (the closure of the semilunar valves), and the diastolic phase of gradual decline in pressure. The difference between the systolic and diastolic pressure, also known as pulse pressure, is a reflection of the stroke volume and the compliance of the arterial system. As the pressure wave travels distally, an increase in systolic amplitude can be noted, whereas the diastolic amplitude decreases initially up to midthoracic level, then increases again. These differences can impact important measurements such as those of aortic gradients. Accordingly, in general, it is advisable to measure the central aortic pressure at the level of the coronary arteries. This also avoids interference with the effect of pressure recovery, which can become relevant in patients with mild to moderate aortic stenosis, particularly when the aorta is small. Elevated a wave (any increase in ventricular filling) Tricuspid stenosis Decreased ventricular compliance as a result of ventricular failure, pulmonic valve stenosis, or pulmonary hypertension D. Cannon a wave Atrial-ventricular asynchrony (atria contract against a closed tricuspid valve, as during complete heart block, following premature ventricular contraction, during ventricular tachycardia, with a ventricular pacemaker) E. Prominent y descent Constrictive pericarditis Restrictive myopathies Tricuspid regurgitation J. Cannon a wave Atrial-ventricular asynchrony (atria contract against a closed mitral valve, as during complete heart block, following premature ventricular contraction, during ventricular tachycardia, or with a ventricular pacemaker) E. Prominent x descent Tamponade Subacute constriction and possibly chronic constriction Right ventricular ischemia with preservation of atrial contractility I. Prominent y descent Constrictive pericarditis Restrictive myopathies Mitral regurgitation J. Elevated systolic pressure Primary pulmonary hypertension Mitral stenosis or regurgitation Congestive heart failure Restrictive myopathies Significant left-to-right shunt Pulmonary disease (pulmonary embolism, hypoxemia, chronic obstructive pulmonary disease) B. Reduced systolic pressure Hypovolemia Pulmonary artery stenosis Subvalvular or supravalvular stenosis Ebstein anomaly Tricuspid stenosis C. End-diastolic pressure elevated Hypervolemia Congestive heart failure Diminished compliance Hypertrophy Tamponade Regurgitant valvular disease Pericardial constriction D. Diminished or absent a wave Atrial fibrillation or flutter Tricuspid or mitral stenosis Tricuspid or mitral regurgitation when ventricular compliance is increased F. Dip and plateau in diastolic pressure wave Constrictive pericarditis Restrictive myopathies Right ventricular ischemia Acute dilation associated with tricuspid or mitral regurgitation G. Systolic pressure elevated Systemic hypertension Arteriosclerosis Aortic insufficiency B. Widened pulse pressure Systemic hypertension Aortic insufficiency Significant patent ductus arteriosus Significant rupture of sinus of Valsalva aneurysm D. Reduced pulse pressure Tamponade Congestive heart failure Cardiogenic shock Aortic stenosis E. Pulsus paradoxus Constrictive pericarditis Tamponade Obstructive airway disease Pulmonary embolism G. Spike-and-dome configuration Obstructive hypertrophic cardiomyopathy Cardiac Output Measurements Although extremely important, often requested and tested, cardiac output measurements represent only estimates of the true cardiac output on the basis of several assumptions. Three methods are used in the catheterization laboratory: thermodilution, Fick, and ventriculography. Thermodilution Method Thermodilution is based on the principle of washout of a temperature change induced by injection of a defined fluid volume cooler than the body temperature. In practice a bolus of liquid (usually 10 mL of normal saline kept at room temperature) is injected into the proximal port of the catheter, and the change in temperature from baseline is measured by a thermistor at the distal end of the catheter and displayed as a function over time. Cardiac output correlates inversely with the area under the curve and can be calculated when the temperature and specific gravity of the injectate and the blood as well as the volume of the injectate are known (eFig.
On occasion buy discount prothiaden, coronary artery catheterization may be required discount prothiaden 75mg mastercard, and as for other vasculitides buy generic prothiaden canada, it should be used cautiously in those suspected of having active coronary arteritis. When possible, steps should be taken to suppress disease activity with immunosuppressive therapy before angiography. Coronary arteritis can cause multiple small areas of myocardial infarction, which often remain clinically silent until the development of congestive cardiac failure. Patients with the most severe disease, including pulmonary hemorrhage, severe cardiac disease, or significant renal impairment, receive pulsed intravenous cyclophosphamide to induce remission over the first 3 to 6 months. In less severe limited disease, remission can 43 be achieved reliably with prednisolone in combination with azathioprine or methotrexate. Nonetheless, clinically significant pericarditis develops in fewer than 30% of patients. The reported prevalence ranges from 11% to 85%, depending on the type of study used to detect disease. Pericarditis is diagnosed by echocardiography, which detects pericardial thickening or small effusions in up to 50% of these patients. The symptoms are typically mild and consist of chest pain, which is worse on lying flat, and dyspnea, which may have a pleuritic component. Complicated pericarditis is rare, and in only 1% to 2% is the effusion sufficiently large to cause cardiac tamponade. Hemodynamically significant pericarditis, although reported, is extremely rare in patients being treated with antirheumatic therapy. Following an initial vascular inflammatory phase, the predominant lesion is 46 fibrosis, which affects multiple organs. Echocardiography typically demonstrates small pericardial effusions, which are rarely hemodynamically significant. Pericardial Fluid Analysis Analysis of pericardial fluid is rarely useful diagnostically unless infective pericarditis is suspected. Treatment In most cases a small pericardial effusion appears on a routine chest radiograph or echocardiogram and requires no specific treatment. Recurrent cases, in particular, require further optimization of the regular immunosuppressive therapy. Pericardial fluid accumulation may be sufficient to cause hemodynamic compromise and even cardiac tamponade requiring pericardiocentesis or, in recurrent cases, a pericardial window. For immunosuppressed patients, pericardial fluid should be analyzed for an infective cause. Advice should be sought from a microbiologist to ensure that the correct specimens are sent, including those required to exclude tuberculosis. Although most commonly present in those with an established rheumatic disease, myocarditis may be an initial feature requiring consideration of these conditions in the differential diagnosis of those with unexplained heart failure. The most common symptom of myocarditis is recent-onset exertional dyspnea with evidence 47 of hypoxia. A patient rarely presents with severe heart failure at the initial evaluation, and echocardiography usually reveals relatively modest changes in ventricular size and function. Other potential causes of heart failure include hypertension, ischemic heart disease, valvular heart disease, and complications associated with renal failure. The initial symptoms of myocarditis vary from low-grade fever, dyspnea, and palpitations to signs of severe heart failure. Functional abnormalities may include segmental, regional, or global wall motion abnormalities; chamber dilation; and a reduced ejection fraction. Following symptomatic deterioration, the echocardiogram was repeated 6 days later and demonstrated markedly increased thickening of the left ventricular wall with a bright signal suggestive of inflammatory infiltration (C and D). These findings were associated with substantial deterioration in left ventricular function. Histopathologic analysis typically reveals small focal areas of fibrinoid necrosis with infiltration of lymphocytes and plasma cells, along with evidence of the deposition of immune complexes closely associated with myocyte bundles. Immunofluorescent studies may reveal granular staining and deposition of complement in and around myocardial blood vessels. Echocardiography may demonstrate impaired diastolic and systolic function and a reduced ejection fraction, occasionally severe enough to cause cardiac failure. Reduced coronary flow reserve occurs commonly, and subclinical myocardial ischemia probably contributes importantly to the ventricular dysfunction. Myositis Polymyositis and dermatomyositis affect the proximal skeletal muscles and can cause severe weakness. In dermatomyositis, additional characteristic cutaneous manifestations include a violaceous heliotrope rash, Gottron papules, and periungual erythema. In pediatric cases, subcutaneous calcification is common and vasculitis may lead to severe gut ischemia and hemorrhage. In adults, particularly those older than 60 years, dermatomyositis may be paraneoplastic in origin. In severe cases, myositis involves the myocardium and pharyngeal or respiratory muscles and can be life-threatening. Creatine kinase levels rise markedly, and electromyography demonstrates fibrillation and polyphasic action potentials. Magnetic resonance imaging of the proximal limb muscles helps identify the muscles involved and most amenable + to biopsy. Echocardiography may reveal ventricular dysfunction, whereas endomyocardial biopsy specimens demonstrate interstitial and perivascular lymphocytic infiltrates, contraction band necrosis, variable cardiomyocyte size, and degeneration and patchy fibrosis. Overt cardiac failure is rare; more common are rhythm and conduction abnormalities, including left anterior hemiblock and right bundle branch block. Treatment Cardiac failure following myocarditis associated with autoimmune disease is treated with standard protocols and supportive interventions (see Chapter 25). Management of myocarditis complicating dermatomyositis or polymyositis uses a similar approach. Because high-dose corticosteroids increase the risk for a renal crisis, early use of intravenous cyclophosphamide is favored. Valvular Heart Disease Clinically significant valvular disease can complicate many rheumatic diseases. Mechanisms may include direct damage to cardiac valve leaflets or aortic valve regurgitation as a consequence of aortitis affecting the ascending aorta (see also Section 8). Verrucous endocarditis (Libman-Sacks endocarditis) and nonspecific valvular thickening occur most commonly. Libman-Sacks lesions typically affect both valve surfaces, most commonly the mitral valve. Active valve lesions contain immunoglobulins, fibrin clumps, areas of focal necrosis, and a leukocytic infiltrate, whereas older healed lesions exhibit vascular fibrous tissue predisposing to scarring and valve leaflet deformity. Echocardiography can help distinguish Libman-Sacks endocarditis from infectious endocarditis, an important consideration in immunosuppressed patients.
In bacterial nism of tension headache is uncertain but is related to 230 Chapter 19 • Headache sustained muscle contraction generic 75mg prothiaden mastercard. Tension headache pro- cycles of days or weeks with remission lasting months duces a bilateral pain prothiaden 75mg fast delivery, general or localized buy prothiaden american express, often de- to years. Associated symptoms include ipsilateral rhinor- scribed as a frontotemporal band-like distribution. The rhea, conjunctival injections, facial sweating, ptosis, and discomfort is described as a mild to moderate, non- eyelid edema. Alcohol ingestion, stress, or vasodilation throbbing pain, tightness, or pressure with a gradual secondary to wind or heat exposure may precipitate onset. Benign Exertional Headache These headaches occur suddenly and are related Migraine Without Aura (Common) to coughing, sneezing, straining, running, or orgasm. About 20% of adults experience migraines, and epi- Headache is the result of stretching the pain-sensitive sodes are not uncommon in children as young as structures in the posterior fossa. The onset is sudden and “splitting,” and and most often accompanied by nausea, photophobia, pain may last from seconds up to 30 minutes. Migraine headaches are Secondary Headaches most commonly found in adults 25 to 34 years of age Infectious Origin and are rare during pregnancy. Sinusitis is frequently associated with a sore present when attacks occur more than 15 days in throat irritated by postnasal discharge, facial or tooth a month. Migraine With Aura (Classic) There frequently is a cough that worsens in a lying Neurological signs that indicate cortical and/or brainstem position, morning periorbital swelling, fever, malaise, involvement precede classic migraine headaches. Ethmoid sinusitis pro- pain may be associated with photophobia, phonophobia duces medial orbit pain. Patients with dental abscess, precedes but may accompany a headache or occur with- nerve root dysfunction, or infection may have head- out headache. Tenderness elicited by tapping on the maxillary teeth Mixed Headache with a tongue blade may indicate dental root infection Mixed headaches are a combination of muscular con- or maxillary sinusitis. The headache is reveal ulceration or infection of pain-sensitive struc- experienced as a throbbing, constant pain during wak- tures in the oral mucosa and gingiva. Family history of migraine is not sensitive structures in the oropharynx, leading to uncommon. Recurrent otitis media with sequelae Cluster Headache of mastoiditis or chronic infection may result in head- Cluster headaches are of vascular origin and are less ache. Bacterial meningitis begins as bacteria The pain is unilateral, ocular, or periocular, and de- colonize in the nasopharynx and enter the central ner- scribed as burning, piercing, or neuralgic. Cluster vous system through the dural venous sinuses or cho- headaches occur more often in men and last 15 minutes roid plexus into the subarachnoid space. The episodic recurrences are “clustered” in organisms in adults are Staphylococcus pneumoniae Chapter 19 • Headache 231 and meningitidis. In children, common organisms are ciliary branches of the internal carotid artery. Other symptoms include fever, malaise, anorexia, systemic toxicity and mental status changes (encephali- weight loss, and/or polymyalgia rheumatica. In contrast, aseptic meningitis caused by enterovi- jaw pain and face pain are rare but highly suggestive. Left untreated, ill with a severe headache, fever, chills, myalgias, pho- blindness may occur in the other eye. A petechial skin rash may sug- temporal arteritis is an emergency, and the patient needs gest meningeal disease. Patients may progress to coma referral to an emergency center for immediate evalua- and have seizures. Symptoms are nonspecifc occur repeatedly over minutes or hours with a minute and are dose related. Headaches caused by trigeminal neuralgia are comes more severe and is associated with dizziness, stimulated by sensory stimuli to the involved nerves, nausea, fatigue, and dimmed vision. Disorders include demyelinating dis- likely to occur in individuals with type 1 diabetes, but ease (such as multiple sclerosis), infammation, viral can occur in anyone taking oral hypoglycemic agents, illness, metabolic disorders, and toxin exposure. The in younger people who experience reactive hypoglyce- patient has an acute onset of blurred vision with ex- mia, or in people who have ingested excessive amounts traocular motion pain that precedes the visual changes of alcohol. Headache is generalized veals a slightly elevated (hyperemic) disc and a and bilateral and is associated with dizziness and a blurred disc margin. The three upper cervical mares and vivid dreams, night sweats, and a headache nerves are sensory pathways for pain sensation felt in on awakening. Blood glucose levels can confrm the the posterior head and ipsilateral temporal and eye presence of hypoglycemia. Withdrawal from prolonged cause muscle spasms and pressure on other neck struc- use of steroids may cause migraine headaches. Downward pres- dilation and an after effect of rebound vasoconstriction sure on the head makes the pain worse and may cause include hydralazine, alcohol, histamine, nicotinic acid, it to travel down the arms. A mild to moderately severe arteritis is a vasculitis of the ophthalmic and posterior generalized headache may occur after ingestion of 232 Chapter 19 • Headache tyramines (e. A headache with topical acne preparations, menopausal women, diary will help identify the pattern of headache related and individuals ingesting large amounts of vitamin A to specifc foods. Papilledema will be present in many cases, but Cerebrovascular Origin without it, the headache may be diagnosed as mixed Intracranial tumor. A neurology referral is indicated to ensure that no more common in children than adults. Objective severe, deep, and aching in nature, often worse in neurological signs are present in 98% of all children morning and aggravated by coughing or straining. There may be a recent history of head injury, nels are still open, hydrocephalus will cause an enlarge- infections (e. The severity of symptoms from associated with a history of head trauma, exertional bleeding intracranial aneurysms is correlated to the physical activity, or pharmacological anticoagulation. Roser T, Bonfert M, Ebinger F, et al: Primary versus secondary head- Kabbouche M, Cleves C: Evaluation and management of children ache in children: A frequent diagnostic challenge in clinical routine, and adolescents presenting in an acute setting, Semin Pediatr Neuropediatics 44:34, 2013. In contrast, indigestion re- The immediate concern when patients present with fers to pain or discomfort in the upper abdomen heartburn or indigestion is to assess for alarm symp- without radiation that occurs with eating or soon toms that require immediate endoscopy. Heartburn can be a result of gastro- Key Questions esophageal acid refux that occurs as a consequence of l Do you have trouble swallowing? Not all refux results in l Have you had rectal bleeding, blood in your stool, or heartburn, and not all heartburn is caused by refux. Heartburn is different Alarm Symptoms from localized gastric or epigastric burning, which The symptoms of most concern are dysphagia, ody- most likely represents dyspepsia. These eating too fast; stress; excess alcohol; caffeine intake; are alarm symptoms for a serious condition and re- and fatty, greasy, or spicy foods. Dysphagia suggests erosive or Barrett is chronic or recurrent is typically associated with esophagus, or gastric or esophageal cancer.
Based on the results of a single randomized study that demonstrated no significant differences in major outcomes between a lenient rate- control strategy (resting rate <110 beats/min) and a strict rate-control strategy (resting heart rate <80 beats/min purchase discount prothiaden, rate during moderate exercise <110 beats/min) discount prothiaden 75mg amex, a lenient rate-control strategy is reasonable if 2 the patient remains asymptomatic and left ventricular systolic function is not compromised purchase discount prothiaden online. However, strict rate control often still is an appropriate goal for relief of symptoms, improvement in functional capacity, and avoidance of tachycardia-induced cardiomyopathy during long-term follow-up. The one drug that stands out as having higher efficacy than the others is amiodarone. Risk factors for this type of proarrhythmia include female gender, left ventricular dysfunction, and hypokalemia. Drugs most likely to result in ventricular proarrhythmia are quinidine, flecainide, sotalol, and dofetilide. In controlled studies, these agents increased the risk of ventricular tachycardia by a factor of 2 to 6. Adverse drug events or side effects resulting in discontinuation of drug therapy are fairly common with 37 rhythm-control drugs, with discontinuation rates reported to be as high as 40%. In patients with substantial left ventricular hypertrophy (left ventricular wall thickness >15 mm), the hypertrophy heightens the risk of 2 ventricular proarrhythmia, and the safest choices for drug therapy are amiodarone and dronedarone. After approval, the categories of patients in which dronedarone is contraindicated expanded based on the results of a 38 randomized clinical trial that was discontinued prematurely because of major adverse drug effects. Success rates greater than 95% are attainable when the arrhythmia substrate is well defined, localized, and temporally stable. Circumferential antral ablation was performed around the left and right pulmonary veins. Each one of the pink, red, and yellow tags represents a site at which radiofrequency energy was delivered. A 3-month blanking period excludes early recurrences that are caused by a transient inflammatory response or incomplete lesion maturation. However, recurrences continue to occur at a rate of approximately 10% per year at 1 to 3 years, then approximately 51 4% to 5%/year at 3 to 12 years after ablation. The risk of a major complication is more than twofold higher when the annual operator volume is 54 less than 25 cases compared to more than 25 cases. Despite its rarity, this complication is of great concern because it often is lethal. Patients typically present 3 to 14 days after ablation with one of more of the following: dysphagia, odynophagia, fever, leukocytosis, bacteremia, and septic, thrombotic, or air emboli. Computed tomography of the chest with intravenous contrast is the diagnostic test of choice. The presence of contrast in the esophagus or air in the mediastinum or cardiac chambers is indicative of esophageal perforation or fistula formation. Monitoring of the position of the esophagus and intraluminal esophageal temperature monitoring have been used to prevent esophageal injury during ablation along the posterior wall. Although these maneuvers may reduce the risk, they clearly do not prevent all cases of esophageal injury, since 90% of patients with an esophageal perforation had undergone monitoring of the esophageal position or 56 temperature. Based on the results of a recent global survey, 72% of patients with an esophageal perforation had evidence of an atrial-esophageal fistula, and mortality among these patients was 79%. In contrast, among the 28% of patients with an esophageal perforation who did not have an atrial-esophageal fistula, 56 mortality was 13%. This highlights the importance of early diagnosis and treatment of esophageal perforations. Early surgical intervention is appropriate regardless of whether an atrial-esophageal fistula is present. Cryoenergy is delivered through the entire distal half of the second-generation cryoballoon catheter currently in clinical use. The 28-mm balloon (arrows) is inflated, and there is no leakage of contrast injected through the lumen of the cryoballoon catheter into the vein (asterisks). This indicates complete occlusion of the vein, a necessary requirement for durable pulmonary vein isolation. B, At 29 seconds into an application of cryoenergy, there is a conduction delay in the pulmonary vein potentials (arrows) followed by their complete disappearance, indicating isolation of the left inferior pulmonary vein (lipv). The most commonly used cryoballoon catheter has a 28-mm diameter when the balloon is fully inflated. Other independent predictors are achieving a balloon temperature of −40°C in less than 60 seconds during an application of cryoenergy and an interval thaw time to 0°C of longer than 64,65 10 seconds on completion of a cryoenergy application. During early experience with the cryoballoon catheter, the incidence of right phrenic nerve injury was approximately 67 10%, with the injury resolving within 12 months in almost all patients. Various strategies are available to monitor diaphragmatic contraction or phrenic nerve function during phrenic nerve pacing, including direct palpation of diaphragmatic contraction and monitoring the diaphragmatic 68 compound motor action potential. The immediate discontinuation of an application of cryoenergy on the first evidence of phrenic nerve injury greatly reduces the risk of long-lasting or permanent injury. In recent experience with the 28-mm cryoballoon catheter, the risk of right phrenic nerve injury is as low as 1. A small number of case reports have made it clear that death from an atrial-esophageal fistula is a potential complication of cryoballoon ablation. Measures to minimize the risk of esophageal injury are appropriate, including the periprocedural use of a proton pump inhibitor and monitoring of intraluminal esophageal temperature during cryoablation. It is common practice to discontinue cryoablation if the esophageal temperature drops to 30°C. The primary safety endpoint was a combination of death, stroke, or a treatment-related serious adverse event. There was also no significant difference in the incidence of primary safety endpoints between the two groups (13. The advantages of cryoballoon ablation include a shorter learning process, less demand for technical expertise in catheter manipulation, and a shorter procedure time. One system has large magnets positioned on each side of the patient and small magnets embedded in the tip of the ablation catheter that allow remote navigation by shifting the magnetic field vectors. The other has an ablation catheter navigated remotely by a robotic steerable sheath system. The advantages of these systems are improved catheter stability, marked reduction in radiation exposure to the operator, and avoidance of the technical challenges of manual catheter manipulation. Atrioventricular node ablation is a technically simple procedure with an acute and long-term success rate of 98% or higher and a very low risk of complications. His bundle pacing can be considered in some patients to avoid problems with right ventricular pacing. The cut-and-sew Cox maze procedure has not been widely performed because it requires cardiopulmonary bypass, is technically difficult, and is associated with a mortality rate of 1% to 2%. These tools allow the surgeon to substitute an ablation line for a surgical incision.
By D. Kamak. Teikyo Marycrest University.