Schaff, Hartzell

AbstractHypertrophic cardiomyopathy (HCM) has a variable clinical presentation and penetrance. Many patients will have a benign course, but others will become symptomatic and develop left ventricular outflow tract obstruction. Echocardiograph remains the standard for diagnosis and assessment of obstruction, but gains are being made in the our understanding of the genetic basis of this condition. Pharmacologic therapy remains the first‐line therapy in the majority of patients, but alcohol septal ablation and surgical septal myectomy may be considered in many patients. Patients should assess both the benefits and risks of each procedure based on the best available current evidence. This paper summarizes important recent developments in HCM diagnosis and therapy.

Background— In the elderly, mitral regurgitation (MR) is frequent, but surgery risks are considered high. Benefits and indications of MR surgery are uncertain in the elderly. Methods and Results— Baseline characteristics, outcome, and trends for surgical results improvement were analyzed in elderly patients (≥75 years of age; n=284) operated on for MR in 1980 to 1995 compared with younger patients (65 to 74 years of age, n=504; and <65 years of age, n=556). Preoperatively, class III to IV symptoms, atrial fibrillation, coronary disease, creatinine, and comorbidity index were more severe in elderly patients (all P <0.002). In the long term after surgery, observed survival stratified by age (≥75, 65 to 74, <65 years) was lower in elderly than in younger patients (at 5 years, 57±3%, 73±2%, and 85±2%, respectively; P <0.001), but ratios of observed to expected survival were similar (83%, 85%, and 88%, respectively). In multivariate analysis adjusted to expected survival, elderly patients showed no difference in life expectancy restoration compared with younger patients (adjusted hazard ratio, 0.89; 95% confidence interval, 0.73 to 1.30; P =0.54). Temporal trends showed that risk of operative mortality, although higher in elderly patients ( P <0.001), declined markedly for all ages (27% to 5% in those ≥75 years of age, P <0.01; 21% to 4% in those 65 to 74 years of age, P <0.01; and 7% to 2% in those <65 years of age, P =0.06), with a parallel decline in low cardiac output and length of hospital stay. Over time, valve repair feasibility increased in all age groups (30% to 84% overall and 31% to 93% in degenerative MR; P <0.0001). Conclusions— Elderly patients undergoing MR surgery display more severe preoperative characteristics and incur higher operative risks than younger patients. However, restoration of life expectancy after surgery is similar in elderly and younger patients, and outstanding recent surgical improvements particularly benefited elderly patients. Thus, elderly patients with MR can now carefully be considered for surgery before refractory heart failure is present.

Background—There are few data regarding medium-term outcome of coronary artery bypass grafting (CABG) in patients with severe left ventricular (LV) systolic dysfunction, particularly in the modern era, and even less assessing preoperative factors that might identify patients at highest risk.Methods and Results—Three hundred seventy-nine consecutive patients with LV ejection fraction ≤35%, who underwent isolated first CABG between 1995 and 1999 were studied. Potential preoperative and perioperative predictors of outcome were recorded and patients followed-up for a median of 3.8 years. The primary study end-point was all-cause mortality. The 30-day, 1-year, and 3-year survival rates were 94.5%, 88%, and 81%, respectively. The independent predictors of mortality were preoperative estimated glomerular filtration rate (hazard ratio [HR], 0.98; 95% confidence interval [CI], 0.97 to 0.99 per mL/min/1.73m2;P<0.001) and age (HR, 1.03; 95% CI, 1.01 to 1.06 per year;P=0.005).Conclusions—Patients with significant LV systolic dysfunction undergoing isolated CABG using contemporary techniques have a good medium-term survival. Renal dysfunction is the strongest independent predictor of mortality.

Background— The impact of aortic prosthesis-patient mismatch (P-PtM) on long-term survival is unclear. Methods and Results— Between 1985 and 2000, 388 patients at Mayo Clinic in Rochester, Minn, underwent aortic valve replacement (AVR) with 19- or 21-mm St Jude Medical prostheses and had transthoracic echocardiography within 1 year after AVR. Mean age of patients was 62±13 years; 69% were female. Prosthesis effective orifice area (EOA) was derived from the continuity equation. P-PtM was classified as severe (indexed EOA ≤0.60 cm 2 /m 2 ), moderate (0.60 cm 2 /m 2 <indexed EOA≤0.85 cm 2 /m 2 ), or not hemodynamically significant (indexed EOA >0.85 cm 2 /m 2 ). P-PtM was severe in 66 patients (17%), moderate in 168 (43%), and not hemodynamically significant in 154 (40%). Patients with severe P-PtM had a significantly larger body surface area ( P <0.0001), higher mean gradient ( P <0.0001), lower preoperative ( P <0.0001) and postoperative ( P <0.0001) ejection fractions, and lower stroke volume ( P <0.0001) and more often received a 19-mm prosthesis ( P =0.0008) than patients with moderate or no hemodynamically significant mismatch. For patients with severe mismatch, 5-year survival rates (72±6%) and 8-year survival rates (41±8%) were significantly less than for patients with moderate mismatch (80±3% and 65±5%; P =0.026) or no hemodynamically significant mismatch (85±3% and 74±5%; P =0.002). On multivariate analysis after adjustment for other predictors of outcome, severe mismatch was associated with higher mortality (hazard ratio 2.18; 95% confidence interval 1.24 to 3.85; P =0.007) and higher incidence of congestive heart failure (hazard ratio 3.1; 95% confidence interval 1.3 to 7.4; P =0.009) than no hemodynamically significant mismatch. Conclusions— Severe P-PtM is an independent predictor of higher long-term mortality and congestive heart failure in patients with small St Jude Medical aortic valve prostheses. For patients undergoing AVR who are at risk of severe mismatch, every effort should be made to use a larger prosthesis or to consider a prosthesis with a larger EOA.

Background— The long-term prognosis of patients who develop carcinoid heart disease and the effect of cardiac surgery on outcome are not well established. Methods and Results— In this retrospective study, we identified 200 patients with carcinoid syndrome referred for echocardiography in whom the diagnosis of carcinoid heart disease was confirmed. Patients were divided into 3 groups of similar size according to the date from first diagnosis of carcinoid heart disease. Group A comprised patients diagnosed from 1981 through June 1989; group B, diagnosed July 1989 through May 1995; and group C, June 1995 through 2000. The end point was all-cause mortality. Median survival was significantly lower in group A (1.5 years, 95% CI 1.1 to 1.9 years) compared with groups B (3.2, 95% CI 1.3 to 5.1 years) and C (4.4, 95% CI 2.4 to 7.1 years; P =0.009). In a multivariate model adjusted for treatment and clinical characteristics, the risk of death in groups B (hazard ratio 0.67, 95% CI 0.46 to 0.99, P =0.04) and C (hazard ratio 0.61, 95% CI 0.39 to 0.92, P =0.006) was significantly reduced relative to group A. Cardiac surgery was performed in 87 patients. When cardiac surgery was included as a time-dependent covariate in a multivariate analysis, it was associated with a risk reduction of 0.48 (95% CI 0.31 to 0.73, P <0.001), whereas the time period of diagnosis was no longer significant. Conclusions— The prognosis of patients with recognized carcinoid heart disease has improved over the past 2 decades at our institution. This change in survival may be related to valve replacement surgery.

Background— Sinus venosus atrial septal defect (SVASD) differs from secundum atrial septal defect by its atrial septal location and its association with anomalous pulmonary venous connection (APVC). Data on long-term outcome after surgical repair are limited. Methods and Results— We reviewed outcomes of 115 patients (mean age±SD 34±23 years) with SVASD who had repair from 1972 through 1996. APVC was present in 112 patients (97%). Early mortality was 0.9%. Complete follow-up was obtained for 108 patients (95%) at 144±99 months. Symptomatic improvement was noted in 83 patients (77%), and deterioration was noted in 17 patients (16%). At follow-up, 7 (6%) of 108 patients had sinus node dysfunction, a permanent pacemaker, or both, and 15 (14%) of 108 patients had atrial fibrillation. Older age at repair was predictive of postoperative atrial fibrillation ( P =0.033). No reoperations were required during follow-up. Survival was not different from expected for an age- and sex-matched population. Clinical improvement was more common with older age at surgery ( P =0.014). Older age at repair ( P =0.008) and preoperative New York Heart Association class III or IV ( P =0.038) were independent predictors of late mortality. Conclusions— Operation for SVASD is associated with low morbidity and mortality, and postoperative subjective clinical improvement occurs irrespective of age at surgery. Postoperative atrial fibrillation appears to be related to older age at operation. SVASD repair achieves survival similar to that of a matched population and should be considered whenever repair may impact survival or symptoms.

Background— The incidence, determinants, and outcome of postoperative atrial fibrillation (AF) after surgery for mitral regurgitation (MR) are poorly defined but may have important implications for timing of mitral valve surgery. Methods and Results— In 762 patients in sinus rhythm with no AF history undergoing MR surgical correction, we examined the rates and prognostic implications of postoperative AF for early AF (within 2 weeks postoperatively) and late AF (>2 weeks after surgery). During postoperative follow-up, 180 patients (24%) experienced new AF (early AF in 136 and late AF in 111). Isolated early AF without recurrence was observed in 69 patients characterized by high angina class and lower left ventricular ejection fraction but no significant left atrial (LA) enlargement. However, overall early AF predicted late AF: 62±5% of patients with early AF had late AF at 10 years compared with 9±1% of patients without early AF ( P <0.0001). Large LA size strongly and independently predicted early AF ( P =0.01) and late AF ( P =0.003). For late AF, the predictive value of an enlarged LA was cumulative to that of early AF. Postoperative AF was associated with an increased subsequently higher risk of stroke or congestive heart failure (adjusted risk ratio=1.46 [1.04 to 2.05], P =0.03). Conclusions— Postoperative AF is common after surgical correction of MR in patients with no prior history of AF and is associated with increased subsequent morbidity. LA enlargement is independently predictive of postoperative AF and as such, should be integrated into the clinical decision-making process in patients with MR.

Background— This study evaluated long-term results of aortic root replacement and valve-preserving aortic root reconstruction for patients with aneurysms involving the aortic root. Methods and Results— Two-hundred three patients aged 53±16 years (mean±SD; 153 male, 50 female) underwent elective or urgent aortic root surgery from 1971 to 2000 for an aortic root aneurysm: 149 patients underwent a composite valve conduit reconstruction, and 54 patients underwent valve-preserving aortic root reconstruction. Fifty patients had Marfan syndrome. In-hospital and 30-day mortality was 4.0% (8/203) overall: for a composite valve conduit procedure, the corresponding value was 4.0% (6/149) and for valve-preserving procedure, 3.7% (2/54) ( P =NS). Morbidity included 3 strokes (1%), 10 perioperative myocardial infarctions (5%), and 8 reoperations for bleeding (4%). Actuarial survival at 5, 10, 15, and 20 years was 93% (95% confidence interval [CI] = 88% to 97%), 79% (95% CI = 71% to 87%), 67% (95% CI = 57% to 79%), and 52% (95% CI = 36% to 69%), respectively. Freedom from reoperation was 72% (95% CI = 54% to 86%) at 20 years. Complications with anticoagulation occurred in 29 patients; with valve thrombosis, in 2; and with hemorrhage, in 27 (4 life threatening and 23 minor). Freedom from thromboembolism was 91% (95% CI = 77% to 98%) at 20 years. Freedom from endocarditis was 99% (95% CI = 92% to 100%) at 20 years. Multivariate analysis revealed preoperative mitral valve regurgitation (+3 to 4) and older age to be significant predictors of late death ( P ≤0.005), and Marfan syndrome, initial valve-preserving aortic root reconstruction, and need for a concomitant procedure at initial operation to be significant predictors of the need for reoperation ( P ≤0.01). Conclusions— Aortic root replacement for aortic root aneurysms can be done with low morbidity and mortality. Composite valve conduit reconstruction resulted in a durable result. There were few serious complications related to the need for long-term anticoagulation or a prosthetic valve. Reoperation was most commonly required because of failure of the aortic valve when a valve-preserving aortic root reconstruction was performed or for other cardiac or aortic disease elsewhere.

Background Activation of the inflammatory cascade is thought to account for some of the respiratory dysfunction and prolonged mechanical ventilation associated with cardiopulmonary bypass. The objective of this investigation was to identify whether perioperative steroids or hemofiltration during cardiopulmonary bypass, by their attenuation of inflammation, would reduce duration of mechanical ventilation after cardiac surgery. Methods After Institutional Review Board approval and informed consent, 192 patients scheduled to undergo elective primary coronary artery bypass grafting or valvular replacement or repair were randomized in a double-blind prospective study into three groups. One group (Control) received saline at induction and at 6-h intervals for four doses. Another group (Hemofil) received saline and hemofiltration to obtain 27 ml/kg of hemofiltrate. The final group (Steroid) received 1 g methylprednisolone before anesthesia induction and then 4 mg of dexamethasone at 6-h intervals for four doses. All patients underwent normothermic cardiopulmonary bypass and received propofol for postoperative sedation. Separate two-sample comparisons were performed to compare each experimental group versus the control group using the Wilcoxon rank sum test for continuous variables and Fisher exact test for categorical variables. In all cases, two-tailed P values </= 0.05 were considered statistically significant. Results The median time until the patient reached an intermittent mandatory ventilation of 4/min (258.5 versus 385.0 min, respectively; P = 0.02) and tracheal extubation (352.0 versus 518.0 min; P = 0.03) was significantly reduced for group Hemofil but no different for Steroid compared to Control. Conclusions Hemofiltration and steroids are both previously reported to attenuate the inflammatory response but only hemofiltration reduced time to tracheal extubation for adults after cardiopulmonary bypass in this study.