Sorajja, Paul

Transcatheter aortic valve implantation (TAVI) has emerged as a less invasive and potentially high efficacious procedure for the treatment of high‐risk patients with symptomatic aortic stenosis. Appropriate patient selection for TAVI is a key component to ultimate clinical success. Herein, we describe a patient with left ventricular outflow tract (LVOT) obstruction that became apparent only following relief of aortic stenosis with TAVI. This report highlights the dynamic nature of LVOT obstruction, which was successfully treated in our patient with catheter‐based alcohol septal ablation. The potential to unmask dynamic LVOT obstruction with TAVI should be an important consideration in patient selection for the procedure, and the postoperative assessment of these patients. © 2012 Wiley Periodicals, Inc.

Background— Percutaneous repair has emerged as a potential therapy for patients with prosthetic paravalvular regurgitation. However, there is a relative paucity of data on the feasibility and outcome of this procedure. Methods and Results— All patients in whom percutaneous paravalvular regurgitation closure was attempted at our hospital were identified and included. Under echocardiographic and fluoroscopic guidance, patients underwent implantation of ≥1 an Amplatzer Septal Occluder, Duct Occluder, Muscular Ventricular Septal Defect Occluder, or Vascular Plug II. Percutaneous repair of 141 paravalvular defects was attempted in 115 patients (age, 67±12 years; men, 53%) with heart failure, hemolytic anemia, or both and who were at high risk of open surgery (mean estimated Society of Thoracic Surgeons mortality, 6.9%). Devices were implanted in 125 defects (89% of total defects), including in 19 patients with multiple defects. Because of the complexity of the procedures, wire exteriorization was required in 29 patients. Overall, successful percutaneous closure (defined as ≤1+ residual regurgitation) was achieved in 88 (77%) patients. Procedural time decreased with increasing case experience for percutaneous repair of both perimitral and periaortic defects. Overall, the 30-day complication rate was 8.7% (sudden and unexplained death, 1.7%; stroke, 2.6%; emergency surgery, 0.9%; bleeding, 5.2%). Two devices embolized during the procedure and were retrieved without sequelae. No procedural deaths occurred, but 2 (1.7%) patients died by 30 days. Conclusions— Percutaneous repair of paravalvular prosthetic regurgitation can be performed with a reasonable rate of procedural success and may be an initial therapeutic option, particularly in patients at significant risk for open surgery. Increased case experience is associated with shorter procedural time.

Background— When advanced, heart failure with preserved ejection fraction (HFpEF) is readily apparent. However, diagnosis of earlier disease may be challenging because exertional dyspnea is not specific for heart failure, and biomarkers and hemodynamic indicators of volume overload may be absent at rest. Methods and Results— Patients with exertional dyspnea and ejection fraction >50% were referred for hemodynamic catheterization. Those with no significant coronary disease, normal brain natriuretic peptide assay, and normal resting hemodynamics (mean pulmonary artery pressure <25 mm Hg and pulmonary capillary wedge pressure [PCWP] <15 mm Hg) (n=55) underwent exercise study. The exercise PCWP was used to classify patients as having HFpEF (PCWP ≥25 mm Hg) (n=32) or noncardiac dyspnea (PCWP <25 mm Hg) (n=23). At rest, patients with HFpEF had higher resting pulmonary artery pressure and PCWP, although all values fell within normal limits. Exercise-induced elevation in PCWP in HFpEF was confirmed by greater increases in left ventricular end-diastolic pressure and was associated with blunted increases in heart rate, systemic vasodilation, and cardiac output. Exercise-induced pulmonary hypertension was present in 88% of patients with HFpEF and was related principally to elevated PCWP, as pulmonary vascular resistances dropped similarly in both groups. Exercise PCWP and pulmonary artery systolic pressure were highly correlated. An exercise pulmonary artery systolic pressure ≥45 mm Hg identified HFpEF with 96% sensitivity and 95% specificity. Conclusions— Euvolemic patients with exertional dyspnea, normal brain natriuretic peptide, and normal cardiac filling pressures at rest may have markedly abnormal hemodynamic responses during exercise, suggesting that chronic symptoms are related to heart failure. Earlier and more accurate diagnosis using exercise hemodynamics may allow better targeting of interventions to treat and prevent HFpEF progression.

Background— Myocardial late gadolinium enhancement (LGE) on contrast-enhanced magnetic resonance imaging (CE-MRI) of patients with hypertrophic cardiomyopathy (HCM) has been suggested to represent intramyocardial fibrosis and, as such, an adverse prognostic risk factor. We evaluated the characteristics of LGE on CE-MRI and explored whether LGE among patients with HCM was associated with genetic testing, severe symptoms, ventricular arrhythmias, or sudden cardiac death (SCD). Methods and Results— Four hundred twenty-four patients with HCM (age=55±16 years [range 2 to 90], 41% females), without a history of septal ablation/myectomy, underwent CE-MRI (GE 1.5 Tesla). We evaluated the relation between LGE and HCM genes status, severity of symptoms, and the degree of ventricular ectopy on Holter ECG. Subsequent SCD and appropriate implanted cardioverter defibrillator (ICD) therapies were recorded during a mean follow-up of 43±14 months (range 16 to 94). Two hundred thirty-nine patients (56%) had LGE on CE-MRI, ranging from 0.4% to 65% of the left ventricle. Gene-positive patients were more likely to have LGE ( P <0.001). The frequencies of New York Heart Association class ≥3 dyspnea and angina class ≥3 were similar in patients with and without LGE (125 of 239 [52%] versus 94 of 185 [51%] and 24 of 239 [10%] versus 18 of 185 [10%], respectively, P =NS). LGE-positive patients were more likely to have episodes of nonsustained ventricular tachycardia (34 of 126 [27%] versus 8 of 94 [8.5%], P <0.001), had more episodes of nonsustained ventricular tachycardia per patient (4.5±12 versus 1.1±0.3, P =0.04), and had higher frequency of ventricular extrasystoles/24 hours (700±2080 versus 103±460, P =0.003). During follow-up, SCD occurred in 4 patients, and additional 4 patients received appropriate ICD discharges. All 8 patients were LGE positive (event rate of 0.94%/y, P =0.01 versus LGE negative). Two additional heart failure-related deaths were recorded among LGE-positive patients. Univariate associates of SCD or appropriate ICD discharge were positive LGE ( P =0.002) and presence of nonsustained ventricular tachycardia ( P =0.04). The association of LGE with events remained significant after controlling for other risk factors. Conclusions— In patients with HCM, presence of LGE on CE-MRI was common and more prevalent among gene-positive patients. LGE was not associated with severe symptoms. However, LGE was strongly associated with surrogates of arrhythmia and remained a significant associate of subsequent SCD and/or ICD discharge after controlling for other variables. If replicated, LGE may be considered an important risk factor for sudden death in patients with HCM.

Background— The clinical efficacy of alcohol septal ablation for drug-refractory hypertrophic cardiomyopathy remains unclear. This study examines the outcome of alcohol septal ablation performed at a tertiary hypertrophic cardiomyopathy referral center. Methods and Results— Among 601 patients with severely symptomatic obstructive hypertrophic cardiomyopathy referred for alcohol septal ablation or myectomy from 1998 to 2006, 138 patients (median age, 64 years; 39% men) chose to undergo ablation. Procedural complications included death in 1.4%, sustained ventricular arrhythmias in 3%, tamponade in 3%, and pacemaker implantation in 20%. This rate was higher than a combined complication rate of 5% in age- and gender-matched patients who had undergone septal myectomy at Mayo Clinic ( P <0.0001). Four-year survival free of all mortality was 88.0% (95% confidence interval, 79.4 to 97.5%), which was similar to that of the age- and gender-matched patients who had undergone myectomy ( P =0.18). Six patients had documented ventricular arrhythmias after ablation, 4 of whom had successful intervention. Four-year survival free of death and severe New York Heart Association class III/IV symptoms after septal ablation was 76.4%, and 71 patients (51%) became asymptomatic. Myectomy patients ≤65 years of age had significantly better survival free of death and severe symptoms ( P =0.01). Conclusions— Alcohol septal ablation is an efficacious procedure if performed in an experienced institution and may resolve symptoms in a subset of patients with obstructive hypertrophic cardiomyopathy. However, the procedural complication rate exceeds that of myectomy. Patients ≤65 years of age have better symptom resolution with myectomy. No impairment in short-term survival was noted in this nonrandomized study, but the long-term outcome remains unknown.

Background— Diastolic dysfunction is a major pathophysiological abnormality in hypertrophic cardiomyopathy (HCM). Doppler echocardiographic parameters correlate with left ventricular (LV) filling pressures in other diseases, but it is unclear whether these findings apply to patients with HCM, who have multiple complex interrelated events leading to diastolic dysfunction. This study compares Doppler echocardiographic estimates of filling pressures to direct measurements of left atrial pressure (LAP) via catheterization in 100 patients with HCM. Methods and Results— One hundred patients who were symptomatic with HCM (New York Heart Association class III/IV, 82%) underwent measurement of early diastolic transmitral flow velocity (E) and mitral annular velocities (e′) with the use of transthoracic echocardiography within 48 hours of cardiac catheterization with direct measurement of LAP. In a subset of 42 patients, echocardiographic and catheterization measurements were performed simultaneously. Mean LAP directly correlated with medial E-e′ ratio in the overall population ( r =0.44, P <0.0001) and also in the subgroup of patients who had simultaneous echocardiographic and catheterization studies ( r =0.28, P =0.07). However, scatter was present. A calculated mean LV filling pressure was derived from the E-e′ ratio with the use of a previously described regression equation, and the 95% confidence limits of agreement with measured mean LAP exceeded ±18 mm Hg both for the overall group and for the subgroup who had simultaneous studies. Similar results were obtained with the lateral E-e′ ratio. Only 1 patient had a previously defined “normal” E-e′ ratio of <8. Conclusions— In symptomatic patients with HCM, Doppler echocardiographic estimates of LV filling pressure with the use of transmitral flows and mitral annular velocities correlate modestly with direct measurement of LAP. Given the complex nature of diastolic dysfunction in HCM, precise characterization of LV filling pressure in an individual patient cannot be determined with the use of these noninvasive parameters.

Background— Little is known about the impact of technological and pharmacological advances on long-term outcome after percutaneous coronary intervention in general clinical practice. Methods and Results— We analyzed in-hospital and long-term outcome of 24 410 percutaneous coronary interventions among 18 575 unique patients who underwent percutaneous coronary intervention at Mayo Clinic over 25 years. The study population was divided into group 1 (n=3708), coronary interventions from 1979 to 1989; group 2 (n=7020), interventions from 1990 to 1996; group 3 (n=10 952), interventions from 1996 to 2003; and group 4 (n=2730), interventions from 2003 to 2004. Despite the fact that patients in groups 3 and 4 were significantly older, sicker, and had greater prevalence of comorbid conditions, heart failure, and previous revascularization than those in groups 1 and 2, procedural success in groups 3 and 4 improved significantly (94%) versus groups 2 (89%) and 1 (78%) ( P <0.001). Significant reduction in in-hospital mortality (groups 4 to 1: 1.8%, 1.7%, 2.6%, 3.0%; P <0.001) and need for emergency bypass surgery (groups 4 to 1: 0.4%, 0.5%, 1.6%, 5%; P <0.001) was noted in groups 3 and 4 compared with groups 1 and 2. Better adherence to currently recommended evidence-based medications for secondary prevention was seen in the recent time periods. After adjustment, significant reduction in follow-up mortality (hazard ratio, 0.81 and 0.74 for groups 3 and 4, respectively); death or myocardial infarction (hazard ratio, 0.80 and 0.75 for groups 3 and 4, respectively); death, myocardial infarction, or revascularization (hazard ratio, 0.76 and 0.58 for groups 3 and 4, respectively) was noted in recent time periods. Conclusions— Despite higher-risk profiles of patients who underwent percutaneous coronary intervention in recent time periods, procedural success as well as in-hospital and long-term outcomes improved significantly over the last 25 years.

Background— Adult patients with hypertrophic cardiomyopathy (HCM) may develop concomitant atherosclerotic coronary artery disease (CAD). There is a paucity of data on the clinical outcomes of HCM patients who have CAD. Methods and Results— We examined the outcome of 433 adult patients with HCM according to the presence and severity of CAD. All patients were aged ≥21 years, had a left ventricular ejection fraction of ≥50%, and were without a history of prior surgical revascularization (mean age, 63 years; 212 men). Compared with HCM patients with mild-to-moderate or no CAD, those with severe CAD demonstrated markedly reduced survival. Ten-year overall survival was 46.1%, 70.5%, and 77.1% for patients with severe, mild-to-moderate, and no CAD, respectively (unadjusted P =0.0001; adjusted P =0.0006). For the end point of cardiac death, this survival was 62.3%, 81.0%, and 80.9% (unadjusted P =0.009; adjusted P =0.004). For the end point of sudden cardiac death, this survival was 77.4%, 93.2%, and 90.3% (unadjusted P =0.01; adjusted P =0.01). The presence of severe CAD also was highly predictive of these events (risk ratio for respective event: 2.31, 2.15, and 2.77) in multivariate models that additionally identified age, prior stroke, hyperlipidemia, and atrial fibrillation as significant covariates. Conclusions— Among adult patients with HCM who undergo coronary angiography, those who have concomitant severe CAD are at increased risk of death. This risk far exceeds historical death rates of CAD patients with normal left ventricular function.