Influence of operator volume on early outcomes of septal myectomy for isolated hypertrophic obstructive cardiomyopathy

Hospital Procedural Volume and Clinical Outcomes Following Septal Reduction Therapy in Obstructive Hypertrophic Cardiomyopathy

Background Prior national data showed a substantial in-hospital mortality in septal myectomy (SM) with an inverse volume-outcomes relationship. This study sought to assess the contemporary outcomes of septal reduction therapy and volume-outcome relationship in obstructive hypertrophic cardiomyopathy. Methods and Results All septal reduction therapy admissions between 2010 to 2019 in the United States were analyzed using the National Readmission Databases. Hospitals were stratified into tertiles of low-, medium-, and high-volume based on annualized procedural volume of alcohol septal ablation and SM. Of 19 007 patients with obstructive hypertrophic cardiomyopathy who underwent septal reduction therapy, 12 065 (63%) had SM. Two-thirds of hospitals performed ≤5 SM or alcohol septal ablation annually. In all SM encounters, 482 patients (4.0%) died in-hospital post-SM. In-hospital mortality was <1% in 1505 (88.4%) hospitals, 1% to 10% in 30 (1.8%) hospitals, and ≥10% in 167 (9.8%) hospitals. There were 63 (3.7%) hospitals (averaging 2.2 SM cases/year) with 100% in-hospital mortality. Post-SM (in low-, medium-, and high-volume centers, respectively), in-hospital mortality (5.7% versus 3.9% versus 2.4%, P=0.003; adjusted odds ratio [aOR], 2.86 [95% CI, 1.70-4.80], P=0.001), adverse in-hospital events (21.30% versus 18.0% versus 12.6%, P=0.001; aOR, 1.88 [95% CI, 1.45-2.43], P=0.001), and 30-day readmission (17.1% versus 12.9% versus 9.7%, P=0.001; adjusted hazard ratio, 1.53 [95% CI, 1.27-1.96], P=0.001) were significantly higher in low- versus high-volume hospitals. For alcohol septal ablation, the incidence of in-hospital death and all other outcomes did not differ by hospital volume. Conclusions In-hospital SM mortality was 4% with an inverse volume-mortality relationship. Mortality post-alcohol septal ablation was similar across all volume tertiles. Morbidity associated with SM was substantial across all volume tertiles.

Ventricular Septal Myectomy for Obstructive Hypertrophic Cardiomyopathy (Analysis Spanning 60 Years Of Practice): AJC Expert Panel

Surgical myectomy remains the time-honored primary treatment for hypertrophic cardiomyopathy patients with drug refractory limiting symptoms due to LV outflow obstruction. Based on >50 years experience, surgery reliably reverses disabling heart failure by permanently abolishing mechanical outflow impedance and mitral regurgitation, with normalization of LV pressures and preserved systolic function. A consortium of 10 international currently active myectomy centers report about 11,000 operations, increasing significantly in number over the most recent 15 years. Performed in experienced multidisciplinary institutions, perioperative mortality for myectomy has declined to 0.6%, becoming one of the safest currently performed open-heart procedures. Extended myectomy relieves symptoms in >90% of patients by ≥ 1 NYHA functional class, returning most to normal daily activity, and also with a long-term survival benefit; concomitant Cox-Maze procedure can reduce the number of atrial fibrillation episodes. Surgery, preferably performed in high volume clinical environments, continues to flourish as a guideline-based and preferred high benefit: low treatment risk option for adults and children with drug refractory disabling symptoms from obstruction, despite prior challenges: higher operative mortality/skepticism in 1960s/1970s; dual-chamber pacing in 1990s, alcohol ablation in 2000s, and now introduction of strong negative inotropic drugs potentially useful for symptom management.

How to build a successful hypertrophic cardiomyopathy team and ensure training the next generation of myectomy surgeons

Transaortic extended septal myectomy is the most reliable method for septal reduction for symptomatic patients with obstructive hypertrophic cardiomyopathy. In addition, surgical management of nonobstructive hypertrophic cardiomyopathy is possible for selected patients with diastolic heart failure and small left ventricular end-diastolic cavity dimensions. These procedures, however, are performed infrequently in many centers, and trainees may not be exposed to the preoperative evaluation and intraoperative management of patients with hypertrophic cardiomyopathy. In this paper, we review what we believe are the central features for creating a successful program for septal myectomy and detail our strategies to optimize instruction in these techniques for residents and fellows.