Marshall L. Jacobs

The automatic implantable cardioverter defibrillator: Efficacy, complications and survival in patients with malignant ventricular arrhythmias

Ninety-four patients underwent surgery for automatic implantable cardioverter-defibrillator implantation. Ninety patients were discharged from the hospital with the device and were followed up for a mean period of 17 +/- 10 months. Forty-six patients experienced at least one discharge of the device under circumstances consistent with a malignant ventricular arrhythmia. One sudden death occurred. Complications included perioperative death (3 patients), post-operative ventricular tachycardia (12 patients) and atrial fibrillation (8 patients), perioperative myocardial infarction (1 patient) and device discharges for sinus tachycardia and supraventricular arrhythmias (17 patients). Six and 12 month survival rates by life table analysis were 98.7 and 95.4%, respectively. Thus, the automatic implantable cardioverter-defibrillator is a highly effective and relatively low risk treatment modality for patients with refractory life-threatening ventricular arrhythmias.

Percutaneous balloon valvotomy for patients with severe mitral stenosis.

Thirty-five patients with severe mitral stenosis underwent percutaneous mitral valvotomy (PMV). There were 29 female and six male patients (mean age 49 +/- 3 years, range 13 to 87). After transseptal left heart catheterization, PMV was performed with either a single- (20 patients) or double- (14 patients) balloon dilating catheter. Hemodynamic and left ventriculographic findings were evaluated before and after PMV. There was one death. Mitral regurgitation developed or increased in severity in 15 patients (43%). One patient developed complete heart block requiring a permanent pacemaker. PMV resulted in a significant decrease in mitral gradient from 18 +/- 1 to 7 +/- 1 mm Hg (p less than .0001) and a significant increase in both cardiac output from 3.9 +/- 0.2 to 4.6 +/- 0.2 liters/min (p less than .001) and in mitral valve area from 0.8 +/- 0.1 to 1.7 +/- 0.2 cm2 (p less than .0001) Effective balloon dilating diameter per square meter of body surface area correlated significantly with the decrease in mitral gradient but did not correlate with the degree of mitral regurgitation. There was no correlation of age, prior mitral commissurotomy or mitral calcification with hemodynamic results. PMV is an effective nonsurgical procedure for patients with mitral stenosis, including those with pliable valves, those with previous commissurotomy, and even those with mitral calcification.

An empirically based tool for analyzing mortality associated with congenital heart surgery

OBJECTIVE Analysis of congenital heart surgery results requires a reliable method of estimating the risk of adverse outcomes. Two major systems in current use are based on projections of risk or complexity that were predominantly subjectively derived. Our goal was to create an objective, empirically based index that can be used to identify the statistically estimated risk of in-hospital mortality by procedure and to group procedures into risk categories. METHODS Mortality risk was estimated for 148 types of operative procedures using data from 77,294 operations entered into the European Association for Cardiothoracic Surgery (EACTS) Congenital Heart Surgery Database (33,360 operations) and the Society of Thoracic Surgeons (STS) Congenital Heart Surgery Database (43,934 patients) between 2002 and 2007. Procedure-specific mortality rate estimates were calculated using a Bayesian model that adjusted for small denominators. Each procedure was assigned a numeric score (the STS-EACTS Congenital Heart Surgery Mortality Score [2009]) ranging from 0.1 to 5.0 based on the estimated mortality rate. Procedures were also sorted by increasing risk and grouped into 5 categories (the STS-EACTS Congenital Heart Surgery Mortality Categories [2009]) that were chosen to be optimal with respect to minimizing within-category variation and maximizing between-category variation. Model performance was subsequently assessed in an independent validation sample (n = 27,700) and compared with 2 existing methods: Risk Adjustment for Congenital Heart Surgery (RACHS-1) categories and Aristotle Basis Complexity scores. RESULTS Estimated mortality rates ranged across procedure types from 0.3% (atrial septal defect repair with patch) to 29.8% (truncus plus interrupted aortic arch repair). The proposed STS-EACTS score and STS-EACTS categories demonstrated good discrimination for predicting mortality in the validation sample (C-index = 0.784 and 0.773, respectively). For procedures with more than 40 occurrences, the Pearson correlation coefficient between a procedures STS-EACTS score and its actual mortality rate in the validation sample was 0.80. In the subset of procedures for which RACHS-1 and Aristotle Basic Complexity scores are defined, discrimination was highest for the STS-EACTS score (C-index = 0.787), followed by STS-EACTS categories (C-index = 0.778), RACHS-1 categories (C-index = 0.745), and Aristotle Basic Complexity scores (C-index = 0.687). When patient covariates were added to each model, the C-index improved: STS-EACTS score (C-index = 0.816), STS-EACTS categories (C-index = 0.812), RACHS-1 categories (C-index = 0.802), and Aristotle Basic Complexity scores (C-index = 0.795). CONCLUSION The proposed risk scores and categories have a high degree of discrimination for predicting mortality and represent an improvement over existing consensus-based methods. Risk models incorporating these measures may be used to compare mortality outcomes across institutions with differing case mixes.

Cardiac surgery in infants with low birth weight is associated with increased mortality: Analysis of the Society of Thoracic Surgeons Congenital Heart Database

OBJECTIVE The evaluation of operative mortality risk for cardiac surgery in infants with low weight is limited. To determine whether low weight is a risk factor for increased mortality, we reviewed the experience within the Society of Thoracic Surgeons Congenital Heart Surgery Database of infants who have undergone surgical correction or palliation for congenital heart disease. METHODS We analyzed mortality in 3022 infants ages 0 to 90 days weighing 1 to 2.5 kg (n = 517) and greater than 2.5 to 4 kg (n = 2505) who underwent cardiac surgery from 2002 through 2004 at 32 participating centers. Patients were grouped according to the primary procedure performed and analyzed according to their weight at the time of surgical intervention. Patients were also analyzed according to Risk Adjustment for Congenital Heart Surgery-1 and Aristotle Basic Complexity scores. RESULTS Compared with infants weighing 2.5 to 4 kg, infants weighing less than 2.5 kg had a significantly higher mortality for the following operations: repair of coarctation of the aorta, total anomalous pulmonary venous connection repair, arterial switch procedure, systemic to pulmonary artery shunt, and the Norwood procedure. Lower infant weight remained strongly associated with mortality risk after stratifying the population by Risk Adjustment for Congenital Heart Surgery-1 levels 2 through 6 and Aristotle Basic Complexity levels 2 through 4. CONCLUSIONS Low weight at the time of surgical intervention is associated with increased mortality in patients undergoing several types of cardiovascular procedures. These data do not allow assessment of specific risks or benefits of any particular treatment strategy. However, they do support the need for prospective analysis of specific treatment strategies for these high-risk patients.

The complex relationship between pediatric cardiac surgical case volumes and mortality rates in a national clinical database

OBJECTIVE We sought to determine the association between pediatric cardiac surgical volume and mortality using sophisticated case-mix adjustment and a national clinical database. METHODS Patients 18 years of age or less who had a cardiac operation between 2002 and 2006 were identified in the Society of Thoracic Surgeons Congenital Heart Surgery Database (32,413 patients from 48 programs). Programs were grouped by yearly pediatric cardiac surgical volume (small, <150; medium, 150-249; large, 250-349; and very large, >or=350 cases per year). Logistic regression was used to adjust mortality rates for volume, surgical case mix (Aristotle Basic Complexity and Risk Adjustment for Congenital Heart Surgery, Version 1 categories), patient risk factors, and year of operation. RESULTS With adjustment for patient-level risk factors and surgical case mix, there was an inverse relationship between overall surgical volume as a continuous variable and mortality (P = .002). When the data were displayed graphically, there appeared to be an inflection point between 200 and 300 cases per year. When volume was analyzed as a categorical variable, the relationship was most apparent for difficult operations (Aristotle technical difficulty component score, >3.0), for which mortality decreased from 14.8% (60/406) at small programs to 8.4% (157/1858) at very large programs (P = .02). The same was true for the subgroup of patients who underwent Norwood procedures (36.5% [23/63] vs 16.9% [81/479], P < .0001). After risk adjustment, all groups performed similarly for low-difficulty operations. Conversely, for difficult procedures, small programs performed significantly worse. For Norwood procedures, very large programs outperformed all other groups. CONCLUSION There was an inverse association between pediatric cardiac surgical volume and mortality that became increasingly important as case complexity increased. Although volume was not associated with mortality for low-complexity cases, lower-volume programs underperformed larger programs as case complexity increased.

Contemporary Patterns of Management of Tetralogy of Fallot: Data From The Society of Thoracic Surgeons Database

BACKGROUND The Society of Thoracic Surgeons Database was queried to ascertain current trends in management of tetralogy of Fallot (TOF) and to determine the prevalence of various surgical techniques. METHODS The study population (n = 3059 operations) was all index operations in 2002-2007, age 0-18 years with Primary Diagnosis of TOF, and Primary Procedure TOF repair or palliation. Patients with Pulmonary Atresia, Absent Pulmonary Valve, and Atrioventricular Canal were excluded. RESULTS 294 patients had initial palliation, including 178 neonates. 2534 patients had repair of TOF as the initial operation (primary repair), including 154 neonates. 217 patients had repair of TOF after prior palliation. Of patients who had primary repair (n = 2534), 975 had repair at 3 to 6 months, 614 at 6 months to 1 year, 492 at 1 to 3 months, and 154 at 0 to 30 days. Of patients who had repair following prior palliation (n = 217), 65 had repair in the first 6 months of life, 111 at 6 months to 1 year, and only 41 (18.9%) at more than 1 year of age. Type of repair: Of 2534 primary repairs, 581 (23%) had no ventriculotomy, 571 (23%) had nontransanular patch, 1329 (52%) had transanular patch, and 53 (2%) had right ventricle to pulmonary artery conduits. Of repairs after prior palliation (n = 217), 20 (9%) had no ventriculotomy, 30 (14%) had nontransanular patch, 144 (66%) had transanular patch, and 24 (11%) had conduits. Discharge mortality (95% confidence interval; CI) was 22 of 294 (7.5%; CI: 4.7%-11.1%) for initial palliation, 33 of 2534 (1.3%; CI: 0.9%-1.8%) for primary repair, and 2 of 217 (0.9%; CI: 0.1%-3.3%) for secondary repair. For neonates, discharge mortality was 11 of 178 (6.2%; CI: 3.1%-10.8%) for palliation and 12 of 154 (7.8%; CI: 4.1%-13.2%) for primary repair. CONCLUSIONS Primary repair in the first year of life is the most prevalent strategy. Despite contemporary awareness of the late consequences of pulmonary insufficiency, ventriculotomy with transanular patch remains the most prevalent technique, both for primary repair and for repair following palliation.

Coarctation of the aorta: Review of 234 patients and clarification of management problems

Abstract Two hundred thirty-four patients with coarctation of the aorta who were managed between 1948 and 1978 were reviewed. Their ages ranged from 1 day to 72 years. Only 6 percent of the patients who had surgical correction between ages 1 and 5 years had residual hypertension. In contrast, 21 percent of those operated on before age 1 year (all with residual or recurrent coarctation), 30 percent of those operated on between ages 6 and 18 years, 47 percent of those operated on between ages 19 and 40 years and 50 percent of patients over 40 age years at the time of operation had residual postoperative hypertension. These data suggest that the optimal time for elective surgical correction of coarctation is between the ages of 1 and 5 years. Preoperative congestive heart failure was present in 67 percent of patients under age 1 year, in 67 percent of those over age 40 years and in only 4 percent of those aged 1 to 40 years. Eight of the 29 infants with preoperative heart failure had residual postoperative failure related in most to associated congenital cardiac anomalies. Six of the 16 patients with preoperative heart failure who were over age 40 years at correction had residual failure, although even in these patients heart failure was improved. Bacterial endocarditis, cerebral vascular accident, myocardial infarction and aortic dissection were present in 2, 6, 3 and 2 percent of patients, respectively; these complications occurred more frequently with advancing age and occurred in 13 patients who had had prior coarctation repair. Additional congenital heart lesions were present in 34 percent of the patients. Of those under age 1 year, 67 percent had a clinically significant patent ductus arteriosus with or without ventricular septal defect or aortic stenosis. After age 1 year, 27 percent of the patients had associated cardiac lesions, and no patient had a clinically significant patent ductus or ventricular septal defect. Aortic stenosis or insufficiency was present in 33 patients. When identified during infancy, aortic stenosis was often clinically significant. Thereafter, only eight patients had clinically significant aortic valve disease at the time of this review, and only two of these patients were younger than age 40 years.

Risk Factors for Mortality and Morbidity After the Neonatal Blalock-Taussig Shunt Procedure

BACKGROUND Perioperative advances have led to significant improvements in outcomes after many complex neonatal open heart procedures. Whether similar improvements have been realized for the modified Blalock-Taussig shunt, the most common palliative neonatal closed-heart procedure, is not known. METHODS Data were abstracted from The Society of Thoracic Surgeons Congenital Heart Surgery Database (2002 to 2009). Inclusion criteria were all neonates who received a modified Blalock-Taussig shunt with or without cardiopulmonary bypass, and with or without concomitant ligation of a patent ductus arteriosus. Discharge mortality was the primary end point. A composite morbidity end point one or more of the following: postoperative extracorporeal membrane oxygenation, low cardiac output, or unplanned reoperation. Associations with patient and procedural variables were assessed with univariable and multivariable analyses. RESULTS The inclusion criteria were met by 1273 patients. The discharge mortality rate was 7.2%, and composite morbidity, as defined, was 13.1%. Primary diagnoses were classified as (1) those potentially amenable to biventricular repair (62%), (2) functionally univentricular hearts (22%), and (3) pulmonary atresia with intact ventricular septum (PA/IVS; 14%), and miscellaneous (2%). Discharge mortality stratified by primary diagnoses was PA/IVS (15.6%), functionally univentricular hearts (7.2%), and diagnoses potentially amenable to biventricular repair (5.1%). Need for preoperative ventilatory support, diagnosis of PA/IVS or functionally univentricular hearts, and any weight less than 3 kg, were risk factors for death. Preoperative acidosis or shock (resolved or persistent) and diagnosis of PA/IVS or functionally univentricular hearts were predictors of composite morbidity. Nearly 33% of the deaths occurred within 24 hours postoperatively, and 75% within the first 30 days. CONCLUSIONS The mortality rate after the neonatal modified Blalock-Taussig shunt remains high, particularly for infants weighing less than 3 kg and those with the diagnosis of PA/IVS.

Variation in Outcomes for Benchmark Operations: An Analysis of The Society of Thoracic Surgeons Congenital Heart Surgery Database

BACKGROUND We evaluated outcomes for common operations in The Society of Thoracic Surgeons Congenital Heart Surgery Database (STS-CHSDB) to provide contemporary benchmarks and examine variation between centers. METHODS Patients undergoing surgery from 2005 to 2009 were included. Centers with greater than 10% missing data were excluded. Discharge mortality and postoperative length of stay (PLOS) among patients discharged alive were calculated for 8 benchmark operations of varying complexity. Power for analyzing between-center variation in outcome was determined for each operation. Variation was evaluated using funnel plots and Bayesian hierarchical modeling. RESULTS Eighteen thousand three hundred seventy-five index operations at 74 centers were included in the analysis of 8 benchmark operations. Overall discharge mortality was: ventricular septal defect (VSD) repair = 0.6% (range, 0% to 5.1%), tetralogy of Fallot (TOF) repair = 1.1% (range, 0% to 16.7%), complete atrioventricular canal repair (AVC) = 2.2% (range, 0% to 20%), arterial switch operation (ASO) = 2.9% (range, 0% to 50%), ASO + VSD = 7.0% (range, 0% to 100%), Fontan operation = 1.3% (range, 0% to 9.1%), truncus arteriosus repair = 10.9% (0% to 100%), and Norwood procedure = 19.3% (range, 0% to 100%). Funnel plots revealed that the number of centers characterized as outliers were VSD = 0, TOF = 0, AVC = 1, ASO = 3, ASO + VSD = 1, Fontan operation = 0, truncus arteriosus repair = 4, and Norwood procedure = 11. Power calculations showed that statistically meaningful comparisons of mortality rates between centers could be made only for the Norwood procedure, for which the Bayesian-estimated range (95% probability interval) after risk-adjustment was 7.0% (3.7% to 10.3%) to 41.6% (30.6% to 57.2%). Between-center variation in PLOS was analyzed for all operations and was larger for more complex operations. CONCLUSIONS This analysis documents contemporary benchmarks for common pediatric cardiac surgical operations and the range of outcomes among centers. Variation was most prominent for the more complex operations. These data may aid in quality assessment and quality improvement initiatives.

Association of Center Volume With Mortality and Complications in Pediatric Heart Surgery

OBJECTIVE: Previous analyses have suggested center volume is associated with outcome in children undergoing heart surgery. However, data are limited regarding potential mediating factors, including the relationship of center volume with postoperative complications and mortality in those who suffer a complication. We examined this association in a large multicenter cohort. METHODS: Children 0 to 18 years undergoing heart surgery at centers participating in the Society of Thoracic Surgeons Congenital Heart Surgery Database (2006–2009) were included. In multivariable analysis, we evaluated outcomes associated with annual center volume, adjusting for patient factors and surgical risk category. RESULTS: A total of 35 776 patients (68 centers) were included. Overall, 40.6% of patients had ≥1 complication, and the in-hospital mortality rate was 3.9%. The mortality rate in those patients with a complication was 9.0%. In multivariable analysis, lower center volume was significantly associated with higher in-hospital mortality. There was no association of center volume with the rate of postoperative complications, but lower center volume was significantly associated with higher mortality in those with a complication (P = .03 when volume examined as a continuous variable; odds ratio in centers with <150 vs >350 cases per year = 1.59 [95% confidence interval: 1.16–2.18]). This association was most prominent in the higher surgical risk categories. CONCLUSIONS: These data suggest that the higher mortality observed at lower volume centers in children undergoing heart surgery may be related to a higher rate of mortality in those with postoperative complications, rather than a higher rate of complications alone.