Faculty Bibliography

BACKGROUND: We have previously reported our 3-step repair for obstructive hypertrophic cardiomyopathy (HCM) consisting of resection of the septum, horizontal plication of the anterior mitral leaflet (AML), and release of abnormal papillary muscle attachments. This article reviews our complete experience with surgical management of HCM to better understand the role and relevance of mitral plication. METHODS: From 1997 to 2011, 132 patients with HCM underwent surgical treatment at our institution. Eighty-two patients (62%) received AML plication based on selection criteria and were classified as group A; patients in group B did not receive plication. All patients underwent preoperative and postoperative echocardiography. Long-term clinical follow-up was obtained by review of scheduled echocardiograms and direct patient interview. RESULTS: The average age of all patients was 55.5 years. Operative mortality was 0%. The mean left ventricular outflow tract (LVOT) gradient decreased from 118+/-41 mm Hg to 6+/-13 mm Hg (p<0.0001). Mean mitral regurgitation improved from 2.4+/-1.0 to 0.5+/-0.7 (p<0.0001). Postoperatively, 96.2% of patients had no residual systolic anterior motion (SAM). Significant improvements in heart failure classification and quality of life scores were noted for all patients. Comparison of groups A and B showed no statistically significant differences in outcomes, complications, or survival. Survival at 1, 5, and 10 years was 98%, 98%, and 92%, respectively. CONCLUSIONS: The heterogeneity of the pathologic process in HCM supports detailed analysis of the septum, mitral leaflets, and subvalvular apparatus. Surgical management of HCM that includes horizontal plication of a lax and elongated AML is safe and results in durable clinical and echocardiographic improvement.

Since its first description in the 1950s, the pathophysiology of hypertrophic cardiomyopathy has been clarified by advanced echocardiographic technologies. Improved pharmacotherapy now successfully treats most afflicted individuals. Along with these advances, surgical management has also evolved, as the role of the mitral valve and the subvalvular structures in causing obstruction has been identified. Over the last 2 decades, a variety of options to surgically manage the complex patient with obstruction have been described. Successful surgical management is dependent on the complete evaluation of the causes of obstruction in the specific individual, as the heterogeneity of the anatomy may confound the direction of therapy. Mitral valve replacement may no longer be necessary in individuals who have a relatively thin septum and instead obstruct from an elongated mitral anterior leaflet or the presence of accessory papillary muscles and chords. Techniques for mitral valve plication have been successfully used with mid- to long-term success. A systematic strategy for the evaluation of obstruction in hypertrophic cardiomyopathy and the various surgical options are summarized in a procedure termed RPR for resection (extended myectomy), plication (mitral valve shortening), and release (papillary muscle manipulation).

Unique genetic characteristics of hypertrophic cardiomyopathy (HCM), including heterogeneity and incomplete penetrance, have made making predictions about prognosis complex. We reviewed data from septal myectomy results as published from 1980 to 2011, most of which come from specialized tertiary care centers. We also performed a retrospective review of 132 consecutive patients who underwent HCM surgery at our institution. At a mean follow-up of 4.2 +/- 3.2 years (range, 3 days to 14.2 years), there were no deaths within 30 days of surgery for our cohort. Over the course of 15 years, 2 deaths occurred in older patients, both of whom had surgery for HCM along with additional cardiac procedures. Age, the presence of comorbidities, and concomitant cardiac procedures were not statistically significant risk factors for mortality. Overall survival at 1, 5, and 10 years was excellent: 99%, 99%, and 92%, respectively. Surgical myectomy has been proven to be a safe and effective procedure for symptomatic obstructive HCM, and it confers excellent survival similar to that of the healthy population.

A 70-year-old male with known hypertrophic cardiomyopathy (HCM) and latent obstruction presented with new onset of cardiogenic shock. He had a new resting left ventricular (LV) outflow gradient of 90 mmHg, and new severe LV systolic dysfunction. Because of rapid deterioration despite medical management he was urgently sent for surgical relief of obstruction, which immediately reversed both the LV dysfunction and shock. A second patient, a 58-year-old male also with hypertrophic cardiomyopathy and latent obstruction presented with collapse, cardiogenic shock, 135 mmHg resting LV outflow gradient and new severe LV systolic dysfunction. His profound shock was irreversible with pharmacologic management, but surgical relief of obstruction reversed both his LV dysfunction and shock. Echocardiography plays a pivotal role in the management of these acutely ill patients.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) has been conventionally associated with increased operative mortality and morbidity after coronary artery bypass grafting. Some studies, however, challenge this association. Moreover, the effect of COPD on long-term survival after coronary artery bypass grafting has not been adequately assessed. Thus, in this clinical setting, both early and late outcome require further examination. METHODS: We studied 3,760 consecutive patients who underwent isolated coronary artery bypass grafting between 1992 and 2002. The propensity for COPD was determined by logistic regression analysis, and each patient with COPD was matched with 3 patients without COPD. Matched groups were compared for early outcome and long-term survival (mean follow-up, 7.6 years). Long-term survival data were obtained from the National Death Index. RESULTS: There were 550 patients (14.6%) with COPD. Multivariate analysis showed that patients with COPD were older and sicker. However, propensity-matched groups did not differ in terms of hospital mortality or major morbidity, although COPD was associated with a slightly longer hospital stay. In contrast, COPD patients had increased long-term mortality, with a hazard ratio of 1.28 (95% confidence intervals, 1.11 to 1.47; p=0.001). Freedom from all-cause mortality at 7 years after CABG was 65% and 72% in matched patients with and without COPD, respectively (p=0.008). In patients with COPD, the hazard estimate was consistently increased up to 9 years postoperatively. CONCLUSIONS: Chronic obstructive pulmonary disease, although not an independent predictor of increased early mortality and morbidity in this series, is a continuing detrimental risk factor for long-term survival.

BACKGROUND: Left ventricular hypertrophy (LVH) can itself contribute to increased rates of cardiovascular events. We sought to determine the impact of LVH on in-hospital and long-term mortality after coronary artery bypass grafting (CABG). METHODS: Between 1992 and 2003, 4140 consecutive patients underwent CABG. Long-term survival data (mean follow-up 7.0 years) were obtained from the National Death Index. The impact of LVH on in-hospital mortality was determined by multivariate logistic regression analysis. Patients with and without LVH were compared by Cox proportional hazard models and risk-adjusted Kaplan-Meier curves. RESULTS: There were 977 patients (23.6%) with LVH. Their mean EuroSCORE was 7.4 +/- 3.4 and there were 40 in-hospital deaths (4.1%) in this group. Multivariate logistic regression showed that patients with LVH had less elective operations, higher Canadian Cardiovascular Society Functional Class, more previous myocardial infarctions and higher percentages of 3-vessel disease, hypertension, current congestive heart failure, malignant ventricular arrhythmias, chronic obstructive pulmonary disease, calcified aorta, low ejection fraction, intravenous nitroglycerine, previous percutaneous coronary interventions and smoking. After adjustment for all available pre, intra and postoperative variables LVH was not an independent predictor for in-hospital mortality (OR 1.04, 95% CIs 0.60-1.81, P = 0.891). Risk-adjusted Kaplan-Meier survival curves showed decreased long-term survival in patients with LVH after the first 3 years (HR 1.24, 95% CIs 1.06-1.44, P = 0.006). CONCLUSIONS: Patients with LVH showed similar in-hospital mortality when compared with patients without LVH. However, LVH was a detrimental risk factor for late mortality, especially after the third postoperative year. These data suggest the need for a more frequent long-term follow-up among patients with LVH undergoing CABG.

BACKGROUND: Abnormal positioning and size of the mitral valve contribute to the systolic anterior motion and mitral-septal contact that are important components of obstructive hypertrophic cardiomyopathy (HCM). The RPR repair (resection of the septum, plication of the anterior leaflet, and release of papillary muscle attachments) addresses all aspects of this complex pathology. This study reports outcomes regarding effectiveness of the RPR repair. METHODS: Fifty consecutive unselected patients (average age, 55.8 years) undergoing RPR repair for obstructive HCM from 1997 to 2007 were studied. Each patient underwent preoperative and postoperative transthoracic echocardiograms to document gradient, ejection fraction, degree of mitral regurgitation, and systolic anterior motion. Intraoperative transesophageal echocardiogram was used to guide all surgical repairs. Clinical follow-up included patient interviews to determine New York Heart Association (NYHA) status. RESULTS: Concomitant operations were performed in 25 patients (50%). Postoperative mortality was 0%. Average mean left ventricular outflow tract gradients decreased from 134 +/- 40 to 2.8 +/- 8.0. Mitral regurgitation improved from a mean of 2.5 to 0.1 (p < 0.001). Average length of stay was 6.9 +/- 2.7 days. NYHA class improved from 3.0 +/- 0.6 to 1.2 +/- 0.5. Follow-up was 100%, with a mean of 2.5 +/- 1.8 years. Average mitral regurgitation at follow-up was 0.9, with no residual systolic anterior motion. CONCLUSIONS: The RPR repair is safe and effective for symptomatic obstructive HCM. Our data support repair of the mitral valve that results in good intermediate outcomes with respect to gradient, mitral regurgitation, and clinical status.