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Rick A Nishimura - One of the best experts on this subject based on the ideXlab platform.
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left ventricular ejection hemodynamics before and after relief of outflow tract obstruction in patients with Hypertrophic Obstructive Cardiomyopathy and valvular aortic stenosis
The Journal of Thoracic and Cardiovascular Surgery, 2020Co-Authors: Hartzell V Schaff, Steve R Ommen, Martin D Abel, Meghana R K Helder, Robert L Frye, Rick A NishimuraAbstract:Abstract Objective There has been debate on the importance and pathophysiologic effects of the dynamic subaortic pressure gradient in Hypertrophic Obstructive Cardiomyopathy. The study was conducted to elucidate the hemodynamic abnormalities associated with the dynamic pressure gradient in Hypertrophic Obstructive Cardiomyopathy. Methods Eight patients with Hypertrophic Obstructive Cardiomyopathy and 7 patients with valvular aortic stenosis underwent a detailed hemodynamic study of pressure flow relationships before and after myectomy or aortic valve replacement during operation. Results In aortic stenosis, the increased gradient after premature ventricular contraction was associated with an increase in peak flow (325 ± 122 mL/s to 428 ± 147 mL/s, P = .002) and stroke volume (75.0 ± 27.3 mL to 88.0 ± 24.0 mL, P = .004), but in Hypertrophic Obstructive Cardiomyopathy peak flow remained unchanged (289 ± 79 mL/s to 299 ± 85 mL/s, P = .334) and stroke volume decreased (45.9 ± 18.7 mL to 38.4 ± 14.4 mL, P = .04) on the postpremature ventricular contraction beat. After myectomy, the capacity to augment stroke volume on the postpremature ventricular contraction beats was restored in patients with Hypertrophic Obstructive Cardiomyopathy (45.6 ± 14.4 mL to 54.4 ± 11.8 mL, P = .002). Conclusions The pressure flow relationship in Hypertrophic Obstructive Cardiomyopathy supports the concept of true obstruction to outflow, with a low but continued flow during late systole, when the ventricular-aortic pressure gradient is the highest. Septal myectomy can abolish obstruction and restore the ability to augment stroke volume, which may explain the mechanism of symptomatic improvement after operation.
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mitral stenosis and Hypertrophic Obstructive Cardiomyopathy an unusual combination
The Journal of Thoracic and Cardiovascular Surgery, 2016Co-Authors: Joonhwa Hong, Hartzell V Schaff, Steve R Ommen, Martin D Abel, Joseph A Dearani, Rick A NishimuraAbstract:Abstract Objective Systolic anterior motion of mitral valve (MV) leaflets is a main pathophysiologic feature of left ventricular outflow tract (LVOT) obstruction in Hypertrophic Obstructive Cardiomyopathy. Thus, restricted leaflet motion that occurs with MV stenosis might be expected to minimize outflow tract obstruction related to systolic anterior motion. Methods From January 1993 through February 2015, we performed MV replacement and septal myectomy in 12 patients with mitral stenosis and Hypertrophic Obstructive Cardiomyopathy at Mayo Clinic Hospital in Rochester, Minn. Preoperative data, echocardiographic images, operative records, and postoperative outcomes were reviewed. Results Mean (standard deviation) age was 70 (7.6) years. Preoperative mean (standard deviation) maximal LVOT pressure gradient was 75.0 (35.0) mm Hg; MV gradient was 13.7 (2.8) mm Hg. From echocardiographic images, 4 mechanisms of outflow tract obstruction were identified: systolic anterior motion without severe limitation in MV leaflet excursion, severe limitation in MV leaflet mobility with systolic anterior motion at the tip of the MV anterior leaflet, septal encroachment toward the LVOT, and MV displacement toward the LVOT by calcification. Mitral valve replacement and extended septal myectomy relieved outflow gradients in all patients, with no death or serious morbidity. Conclusions Patients with mitral stenosis and Hypertrophic Obstructive Cardiomyopathy have multiple LVOT obstruction mechanisms, and MV replacement may not be adequate treatment. We favor septal myectomy and MV replacement in this complex subset of Hypertrophic Obstructive Cardiomyopathy.
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Hypertrophic Obstructive Cardiomyopathy and Uncontrolled Hypertension : A Therapeutic Challenge
Jacc-cardiovascular Interventions, 2016Co-Authors: Abdallah El Sabbagh, Darrell B. Newman, William R. Miranda, Rick A NishimuraAbstract:Hypertrophic Obstructive Cardiomyopathy and concomitant systemic hypertension can present a challenging diagnostic and therapeutic dilemma. Symptoms can occur from increased afterload from both dynamic outflow obstruction as well as the elevated systemic vascular resistance. Treatment of systemic
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Dual Chamber Pacing for Patients With Hypertrophic Obstructive Cardiomyopathy: A Clinical Perspective in 2000
Mayo Clinic proceedings, 2000Co-Authors: John P. Erwin, Rick A Nishimura, Margaret A. Lloyd, A. Jamil TajikAbstract:In some patients with Hypertrophic Cardiomyopathy, the dynamic left ventricular outflow tract Obstructive gradient results in exercise-limiting symptoms of dyspnea, angina, and syncope. Dual chamber pacing has been proposed as a widely available alternative treatment for a subset of patients with symptomatic Hypertrophic Obstructive Cardiomyopathy. Initial studies showed a reduction in gradient and an improvement in symptoms in almost 90% of patients with severe symptoms. We report the Mayo Clinic experience with dual chamber pacing in 38 patients with Hypertrophic Obstructive Cardiomyopathy who had permanent pacemakers implanted for limiting symptoms intractable to medical therapy. After a mean ± SD follow-up of 24±14 months, subjective improvement was reported in 47% of patients. However, there was no statistical difference between the maximal oxygen consumption at last follow-up and AAI pacing (atrial sensing and atrial pacing) (18.6±1.1 mL·kg −1. min −1 ) (ie, when the pacemaker was implanted but not pacing continuously). This article discusses the clinical perspective on the utility of dual chamber pacing for patients with Hypertrophic Obstructive Cardiomyopathy.
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extent of clinical improvement after surgical treatment of Hypertrophic Obstructive Cardiomyopathy
Circulation, 1996Co-Authors: Robert B Mccully, Hartzell V Schaff, Rick A Nishimura, Jamil A Tajik, Gordon K DanielsonAbstract:Background A subgroup of patients with Hypertrophic Obstructive Cardiomyopathy remain severely symptomatic despite optimal medical therapy. Septal myectomy reduces or eliminates left ventricular outflow obstruction and produces marked symptomatic improvement. With the recent advent of alternative methods for treatment of this disorder, such as dual-chamber pacing, it is necessary to establish the risks and benefits of septal myectomy in the modern surgical era. Methods and Results The clinical, ECG, echocardiographic, cardiac catheterization, and surgical data were analyzed for 65 patients 20 to 70 years old with Hypertrophic Obstructive Cardiomyopathy who had surgical treatment between 1986 and 1992. Specific symptoms and overall functional status were evaluated before surgery and at the end of the first postoperative year. Subsequent long-term clinical postoperative follow-up was also obtained. The extent of postoperative improvement was measured by the presence and severity of persistent symptoms, over...
Hartzell V Schaff - One of the best experts on this subject based on the ideXlab platform.
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left ventricular ejection hemodynamics before and after relief of outflow tract obstruction in patients with Hypertrophic Obstructive Cardiomyopathy and valvular aortic stenosis
The Journal of Thoracic and Cardiovascular Surgery, 2020Co-Authors: Hartzell V Schaff, Steve R Ommen, Martin D Abel, Meghana R K Helder, Robert L Frye, Rick A NishimuraAbstract:Abstract Objective There has been debate on the importance and pathophysiologic effects of the dynamic subaortic pressure gradient in Hypertrophic Obstructive Cardiomyopathy. The study was conducted to elucidate the hemodynamic abnormalities associated with the dynamic pressure gradient in Hypertrophic Obstructive Cardiomyopathy. Methods Eight patients with Hypertrophic Obstructive Cardiomyopathy and 7 patients with valvular aortic stenosis underwent a detailed hemodynamic study of pressure flow relationships before and after myectomy or aortic valve replacement during operation. Results In aortic stenosis, the increased gradient after premature ventricular contraction was associated with an increase in peak flow (325 ± 122 mL/s to 428 ± 147 mL/s, P = .002) and stroke volume (75.0 ± 27.3 mL to 88.0 ± 24.0 mL, P = .004), but in Hypertrophic Obstructive Cardiomyopathy peak flow remained unchanged (289 ± 79 mL/s to 299 ± 85 mL/s, P = .334) and stroke volume decreased (45.9 ± 18.7 mL to 38.4 ± 14.4 mL, P = .04) on the postpremature ventricular contraction beat. After myectomy, the capacity to augment stroke volume on the postpremature ventricular contraction beats was restored in patients with Hypertrophic Obstructive Cardiomyopathy (45.6 ± 14.4 mL to 54.4 ± 11.8 mL, P = .002). Conclusions The pressure flow relationship in Hypertrophic Obstructive Cardiomyopathy supports the concept of true obstruction to outflow, with a low but continued flow during late systole, when the ventricular-aortic pressure gradient is the highest. Septal myectomy can abolish obstruction and restore the ability to augment stroke volume, which may explain the mechanism of symptomatic improvement after operation.
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mitral stenosis and Hypertrophic Obstructive Cardiomyopathy an unusual combination
The Journal of Thoracic and Cardiovascular Surgery, 2016Co-Authors: Joonhwa Hong, Hartzell V Schaff, Steve R Ommen, Martin D Abel, Joseph A Dearani, Rick A NishimuraAbstract:Abstract Objective Systolic anterior motion of mitral valve (MV) leaflets is a main pathophysiologic feature of left ventricular outflow tract (LVOT) obstruction in Hypertrophic Obstructive Cardiomyopathy. Thus, restricted leaflet motion that occurs with MV stenosis might be expected to minimize outflow tract obstruction related to systolic anterior motion. Methods From January 1993 through February 2015, we performed MV replacement and septal myectomy in 12 patients with mitral stenosis and Hypertrophic Obstructive Cardiomyopathy at Mayo Clinic Hospital in Rochester, Minn. Preoperative data, echocardiographic images, operative records, and postoperative outcomes were reviewed. Results Mean (standard deviation) age was 70 (7.6) years. Preoperative mean (standard deviation) maximal LVOT pressure gradient was 75.0 (35.0) mm Hg; MV gradient was 13.7 (2.8) mm Hg. From echocardiographic images, 4 mechanisms of outflow tract obstruction were identified: systolic anterior motion without severe limitation in MV leaflet excursion, severe limitation in MV leaflet mobility with systolic anterior motion at the tip of the MV anterior leaflet, septal encroachment toward the LVOT, and MV displacement toward the LVOT by calcification. Mitral valve replacement and extended septal myectomy relieved outflow gradients in all patients, with no death or serious morbidity. Conclusions Patients with mitral stenosis and Hypertrophic Obstructive Cardiomyopathy have multiple LVOT obstruction mechanisms, and MV replacement may not be adequate treatment. We favor septal myectomy and MV replacement in this complex subset of Hypertrophic Obstructive Cardiomyopathy.
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extent of clinical improvement after surgical treatment of Hypertrophic Obstructive Cardiomyopathy
Circulation, 1996Co-Authors: Robert B Mccully, Hartzell V Schaff, Rick A Nishimura, Jamil A Tajik, Gordon K DanielsonAbstract:Background A subgroup of patients with Hypertrophic Obstructive Cardiomyopathy remain severely symptomatic despite optimal medical therapy. Septal myectomy reduces or eliminates left ventricular outflow obstruction and produces marked symptomatic improvement. With the recent advent of alternative methods for treatment of this disorder, such as dual-chamber pacing, it is necessary to establish the risks and benefits of septal myectomy in the modern surgical era. Methods and Results The clinical, ECG, echocardiographic, cardiac catheterization, and surgical data were analyzed for 65 patients 20 to 70 years old with Hypertrophic Obstructive Cardiomyopathy who had surgical treatment between 1986 and 1992. Specific symptoms and overall functional status were evaluated before surgery and at the end of the first postoperative year. Subsequent long-term clinical postoperative follow-up was also obtained. The extent of postoperative improvement was measured by the presence and severity of persistent symptoms, over...
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Mitral regurgitation due to ruptured chordae tendineae in patients with Hypertrophic Obstructive Cardiomyopathy.
Journal of the American College of Cardiology, 1992Co-Authors: Jae K. Oh, Hartzell V Schaff, Stephen L. Kopecky, A. Jamil TajikAbstract:Abstract Mitral valve regurgitation in association with Hypertrophic Obstructive Cardiomyopathy is usually caused by the systolic anterior motion of the anterior mitral leaflet. Recently, five patients were encountered with Hypertrophic Obstructive Cardiomyopathy who had mitral regurgitation due to ruptured chordae tendineae. The diagnosis was confirmed in all patients during operation for left ventricular septal myectomy-myotomy (Morrow procedure). Preoperative identification of ruptured chordae tendineae as the cause of mitral regurgitation was established by transesophageal echocardiography in the three most recent cases. All patients had successful septal myectomy-myotomy for relief of left ventricular outflow obstruction, and mitral valve competence was restored by valve repair rather than by prosthetic valve replacement. The clinical course of these patients illustrates important management considerations as well as the utility of transesophageal echocardiography for diagnosis. Chordal rupture should be considered in the differential diagnosis of mitral regurgitation in patients with Hypertrophic Obstructive Cardiomyopathy, especially in those with acute hemodynamic deterioration.
L Kappenberger - One of the best experts on this subject based on the ideXlab platform.
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Pacing in Hypertrophic Obstructive Cardiomyopathy
European Heart Journal, 1997Co-Authors: L Kappenberger, Cecilia Linde, Claude Daubert, W J Mckenna, E Meisel, Nicolas Sadoul, Lidia Chojnowska, L Guize, Daniel Gras, X JeanrenaudAbstract:Background Uncontrolled studies have shown that short atrioventricular delay dual chamber pacing reduces outflow tract obstruction in Hypertrophic Obstructive Cardiomyopathy. Although the exact mechanism of this beneficial effect is unclear, this seems a promising potential new treatment for Hypertrophic Obstructive Cardiomyopathy. Method In order to evaluate the impact of pacing therapy, we performed a randomized multicentre double-blind crossover (pacemaker activated vs non activated) study to investigate modification of echocardiography, exercise tolerance, angina, dyspnoea and quality of life in 83 patients with a mean age of 53 (range 22–87) years with symptoms refractory or intolerant to classical drug treatment. Results After 12 weeks of activated or inactivated pacing, independent of which phase was first, the pressure gradient fell from 59±36 mmHg to 30±25 mmHg ( P
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pacing in Hypertrophic Obstructive Cardiomyopathy
European Heart Journal, 1997Co-Authors: L Kappenberger, Cecilia Linde, Claude Daubert, W J Mckenna, E Meisel, Nicolas Sadoul, Lidia Chojnowska, L Guize, Daniel Gras, X JeanrenaudAbstract:Background Uncontrolled studies have shown that short atrioventricular delay dual chamber pacing reduces outflow tract obstruction in Hypertrophic Obstructive Cardiomyopathy. Although the exact mechanism of this beneficial effect is unclear, this seems a promising potential new treatment for Hypertrophic Obstructive Cardiomyopathy. Method In order to evaluate the impact of pacing therapy, we performed a randomized multicentre double-blind crossover (pacemaker activated vs non activated) study to investigate modification of echocardiography, exercise tolerance, angina, dyspnoea and quality of life in 83 patients with a mean age of 53 (range 22–87) years with symptoms refractory or intolerant to classical drug treatment. Results After 12 weeks of activated or inactivated pacing, independent of which phase was first, the pressure gradient fell from 59±36 mmHg to 30±25 mmHg ( P <0·001) with active pacing. Exercise tolerance improved by 21% in those patients who at baseline tolerated less than 10 min of Bruce protocol; symptoms of dyspnoea and angina also improved significantly from NYHA class 2·4 to 1·4 and 1·0 to 0·4, respectively ( P <0·007). Quality of life assessment with a validated questionnaire objectivated the subjective improvement. Conclusion Pacemaker therapy is of clinical and haemodynamic benefit for patients with Hypertrophic Obstructive Cardiomyopathy, left ventricular outflow gradient at rest over 30 mmHg who are symptomatic despite drug treatment.
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effects of dual chamber pacing in Hypertrophic Obstructive Cardiomyopathy
The Lancet, 1992Co-Authors: X Jeanrenaud, L KappenbergerAbstract:Abstract Although attempts have been made to treat Hypertrophic Obstructive Cardiomyopathy with right ventricular pacing, the usual treatment for those refractory to medical therapy is open heart surgery. To assess in detail the value of non-surgical therapy the effects of acute and long-term dual-chamber pacing were investigated in 13 patients with Hypertrophic Obstructive Cardiomyopathy refractory to medical treatment. In the first part of the study, atrioventricular (AV) sequential pacing was found to reduce peak subaortic pressure gradient in 12 of the 13 patients, from 82 (SD 42) to 47 (34) mm Hg (p
X Jeanrenaud - One of the best experts on this subject based on the ideXlab platform.
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Pacing in Hypertrophic Obstructive Cardiomyopathy
European Heart Journal, 1997Co-Authors: L Kappenberger, Cecilia Linde, Claude Daubert, W J Mckenna, E Meisel, Nicolas Sadoul, Lidia Chojnowska, L Guize, Daniel Gras, X JeanrenaudAbstract:Background Uncontrolled studies have shown that short atrioventricular delay dual chamber pacing reduces outflow tract obstruction in Hypertrophic Obstructive Cardiomyopathy. Although the exact mechanism of this beneficial effect is unclear, this seems a promising potential new treatment for Hypertrophic Obstructive Cardiomyopathy. Method In order to evaluate the impact of pacing therapy, we performed a randomized multicentre double-blind crossover (pacemaker activated vs non activated) study to investigate modification of echocardiography, exercise tolerance, angina, dyspnoea and quality of life in 83 patients with a mean age of 53 (range 22–87) years with symptoms refractory or intolerant to classical drug treatment. Results After 12 weeks of activated or inactivated pacing, independent of which phase was first, the pressure gradient fell from 59±36 mmHg to 30±25 mmHg ( P
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pacing in Hypertrophic Obstructive Cardiomyopathy
European Heart Journal, 1997Co-Authors: L Kappenberger, Cecilia Linde, Claude Daubert, W J Mckenna, E Meisel, Nicolas Sadoul, Lidia Chojnowska, L Guize, Daniel Gras, X JeanrenaudAbstract:Background Uncontrolled studies have shown that short atrioventricular delay dual chamber pacing reduces outflow tract obstruction in Hypertrophic Obstructive Cardiomyopathy. Although the exact mechanism of this beneficial effect is unclear, this seems a promising potential new treatment for Hypertrophic Obstructive Cardiomyopathy. Method In order to evaluate the impact of pacing therapy, we performed a randomized multicentre double-blind crossover (pacemaker activated vs non activated) study to investigate modification of echocardiography, exercise tolerance, angina, dyspnoea and quality of life in 83 patients with a mean age of 53 (range 22–87) years with symptoms refractory or intolerant to classical drug treatment. Results After 12 weeks of activated or inactivated pacing, independent of which phase was first, the pressure gradient fell from 59±36 mmHg to 30±25 mmHg ( P <0·001) with active pacing. Exercise tolerance improved by 21% in those patients who at baseline tolerated less than 10 min of Bruce protocol; symptoms of dyspnoea and angina also improved significantly from NYHA class 2·4 to 1·4 and 1·0 to 0·4, respectively ( P <0·007). Quality of life assessment with a validated questionnaire objectivated the subjective improvement. Conclusion Pacemaker therapy is of clinical and haemodynamic benefit for patients with Hypertrophic Obstructive Cardiomyopathy, left ventricular outflow gradient at rest over 30 mmHg who are symptomatic despite drug treatment.
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effects of dual chamber pacing in Hypertrophic Obstructive Cardiomyopathy
The Lancet, 1992Co-Authors: X Jeanrenaud, L KappenbergerAbstract:Abstract Although attempts have been made to treat Hypertrophic Obstructive Cardiomyopathy with right ventricular pacing, the usual treatment for those refractory to medical therapy is open heart surgery. To assess in detail the value of non-surgical therapy the effects of acute and long-term dual-chamber pacing were investigated in 13 patients with Hypertrophic Obstructive Cardiomyopathy refractory to medical treatment. In the first part of the study, atrioventricular (AV) sequential pacing was found to reduce peak subaortic pressure gradient in 12 of the 13 patients, from 82 (SD 42) to 47 (34) mm Hg (p
Sherif F Nagueh - One of the best experts on this subject based on the ideXlab platform.
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alcohol septal ablation for the treatment of Hypertrophic Obstructive Cardiomyopathy a multicenter north american registry
Journal of the American College of Cardiology, 2011Co-Authors: Sherif F Nagueh, Bertron M Groves, Leonard Schwartz, Karen M Smith, Andrew Wang, Richard G Bach, Christopher D Nielsen, Ferdinand Leya, John M Buergler, Steven K RoweAbstract:Objectives The purpose of the study is to identify the predictors of clinical outcome (mortality and survival without repeat septal reduction procedures) of alcohol septal ablation for the treatment of patients with Hypertrophic Obstructive Cardiomyopathy. Background Alcohol septal ablation is used for treatment of medically refractory Hypertrophic Obstructive Cardiomyopathy patients with severe outflow tract obstruction. The existing literature is limited to single-center results, and predictors of clinical outcome after ablation have not been determined. Registry results can add important data. Methods Hypertrophic Obstructive Cardiomyopathy patients (N = 874) who underwent alcohol septal ablation were enrolled. The majority (64%) had severe obstruction at rest, and the remaining had provocable obstruction. Before ablation, patients had severe dyspnea (New York Heart Association [NYHA] functional class III or IV: 78%) and/or severe angina (Canadian Cardiovascular Society angina class III or IV: 43%). Results Significant improvement (p Conclusions Variables that predict mortality after ablation, include baseline ejection fraction and NYHA functional class, the number of septal arteries injected with ethanol, post-ablation septal thickness, beta-blocker use, and the number of ablation procedures.
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predictors of outcome after alcohol septal ablation therapy in patients with Hypertrophic Obstructive Cardiomyopathy
Circulation, 2004Co-Authors: Su Min Chang, Nasser Lakkis, Jennifer Franklin, William H Spencer, Sherif F NaguehAbstract:Background— Alcohol septal ablation (ASA) therapy results in clinical and hemodynamic improvement in patients with Hypertrophic Obstructive Cardiomyopathy. However, a subset remains symptomatic afterward, requiring additional procedures. We sought to examine the determinants of an unsatisfactory outcome, defined as unchanged symptoms with <50% reduction of baseline left ventricular outflow tract (LVOT) gradient. Methods and Results— Of 173 consecutive Hypertrophic Obstructive Cardiomyopathy patients who underwent ASA, 39 had an unsatisfactory outcome after the first procedure. Patients with an unsatisfactory outcome had a higher baseline LVOT gradient, fewer septal arteries injected with ethanol, lower peak creatine kinase (CK), smaller septal area opacified by contrast echocardiography, and higher residual gradient in the catheterization laboratory after ASA (all P<0.05). Symptoms, septal thickness, mitral regurgitation severity, and ventricular function were not determinants of outcome. On multiple logi...