Shinobu Itagaki

Survival and Long-term Outcomes Following Bioprosthetic vs Mechanical Aortic Valve Replacement in Patients Aged 50 to 69 Years

IMPORTANCE The choice between bioprosthetic and mechanical aortic valve replacement in younger patients is controversial because long-term survival and major morbidity are poorly characterized. OBJECTIVE To quantify survival and major morbidity in patients aged 50 to 69 years undergoing aortic valve replacement. DESIGN, SETTING, AND PARTICIPANTS Retrospective cohort analysis of 4253 patients aged 50 to 69 years who underwent primary isolated aortic valve replacement using bioprosthetic vs mechanical valves in New York State from 1997 through 2004, identified using the Statewide Planning and Research Cooperative System. Median follow-up time was 10.8 years (range, 0 to 16.9 years); the last follow-up date for mortality was November 30, 2013. Propensity matching yielded 1001 patient pairs. MAIN OUTCOMES AND MEASURES Primary outcome was all-cause mortality; secondary outcomes were stroke, reoperation, and major bleeding. RESULTS No differences in survival or stroke rates were observed in patients with bioprosthetic compared with mechanical valves. Actuarial 15-year survival was 60.6% (95% CI, 56.3%-64.9%) in the bioprosthesis group compared with 62.1% (95% CI, 58.2%-66.0%) in the mechanical prosthesis group (hazard ratio, 0.97 [95% CI, 0.83-1.14]). The 15-year cumulative incidence of stroke was 7.7% (95% CI, 5.7%-9.7%) in the bioprosthesis group and 8.6% (95% CI, 6.2%-11.0%) in the mechanical prosthesis group (hazard ratio, 1.04 [95% CI, 0.75-1.43). The 15-year cumulative incidence of reoperation was higher in the bioprosthesis group (12.1% [95% CI, 8.8%-15.4%] vs 6.9% [95% CI, 4.2%-9.6%]; hazard ratio, 0.52 [95% CI, 0.36-0.75]). The 15-year cumulative incidence of major bleeding was higher in the mechanical prosthesis group (13.0% [95% CI, 9.9%-16.1%] vs 6.6% [95% CI, 4.8%-8.4%]; hazard ratio, 1.75 [95% CI, 1.27-2.43]). The 30-day mortality rate was 18.7% after stroke, 9.0% after reoperation, and 13.2% after major bleeding. CONCLUSIONS AND RELEVANCE Among propensity-matched patients aged 50 to 69 years who underwent aortic valve replacement with bioprosthetic compared with mechanical valves, there was no significant difference in 15-year survival or stroke. Patients in the bioprosthetic valve group had a greater likelihood of reoperation but a lower likelihood of major bleeding. These findings suggest that bioprosthetic valves may be a reasonable choice in patients aged 50 to 69 years.

Bilateral internal mammary artery grafts, mortality and morbidity: an analysis of 1 526 360 coronary bypass operations

Objectives The objective of this study was to investigate the impact of bilateral internal mammary artery (BIMA) on early outcomes after coronary artery bypass grafting. Design Retrospective database analysis. Setting US hospitals. Patients 1 526 360 patients (mean age 65 years, 73% male) from the Nationwide Inpatient Sample from 2002–2008 who underwent isolated coronary artery bypass grafting with at least one internal mammary artery. Interventions Single versus BIMA bypass grafting. Main outcome measures Inhospital mortality, deep sternal wound infection (DSWI). Results The rate of BIMA use was 3.9%. Use of BIMA was independently associated with slightly lower inhospital mortality (unadjusted rate 1.1% vs 1.7%, adjusted OR 0.86, 95% CI 0.79 to 0.93). The DSWI rate was 1.4%. The independent predictors of DSWI were female gender (OR 1.06), congestive heart failure (OR 6.22), chronic pulmonary disease (OR 1.57), obesity (OR 1.17), diabetes mellitus (OR 1.04; OR 1.51 with chronic complication) and chronic renal failure (OR 2.13; OR 2.63 with dialysis). The use of BIMA was not an independent predictor of DSWI (OR 1.03, 95% CI 0.96 to 1.10). BIMA was associated with higher incidence of DSWI in patients with chronic complications of diabetes mellitus (OR 1.90, 95% CI 1.51 to 2.41). Conclusions BIMA grafting is associated with increased risk of DSWI only in patients with severe, chronic diabetes. The incremental morbidity and mortality of DSWI does not justify denial of BIMA in the majority of patients.

Predicting systolic anterior motion after mitral valve reconstruction: using intraoperative transoesophageal echocardiography to identify those at greatest risk

OBJECTIVES We set out to determine if intraoperative pre-bypass transoesophageal echocardiography could assist in predicting which patients are at greatest risk for systolic anterior motion (SAM) after mitral valve repair (MVR). METHODS Three hundred and seventy-five consecutive patients who underwent reconstructive MVR surgery for degenerative disease were included. Data were collected using intraoperative echocardiographic images taken prior to the initiation of cardiopulmonary bypass. Based on the physiology of SAM, we postulated that 11 parameters could be potential risk factors for SAM: left ventricular ejection fraction (LVEF), left ventricular end-systolic dimension, left ventricular end-diastolic dimension (LVEDD), basal septal diameter (basal-interventricular septal diameter in diastole (IVDd)), mid-ventricular septal diameter (mid-IVDd), coaptation-septal distance (c-sept), anterior leaflet height, posterior leaflet height, aorto-mitral angle, mitral annular diameter and left atrial diameter. These parameters were measured and recorded by a blinded single operator. Independent predictors of SAM were identified using multiple logistic regression analysis. RESULTS Of the 375 patients, 345 (92%) did not develop SAM (No-SAM group), while 30 (8%) developed intraoperative or postoperative SAM (SAM group). The mean age was 56.8 ± 12.8 and 56.7 ± 13.8 in the No-SAM and SAM groups, respectively. The incidence of fibroelastic deficiency, forme fruste and Barlows disease was similar in both groups. All patients received a complete annuloplasty ring as part of the repair. There was no statistical difference in the mean ring size used in each group. EF was similar in the No-SAM (56.2% ± 8.1) and SAM (57.0% ± 9.2) P = 0.63) groups. Independent predictors of developing SAM after valve repair were: EDD <45 mm [odds ratio (OR) 3.90; P = 0.028], aorto-mitral angle <120° (OR 2.74; P = 0.041), coaptation-septum distance <25 mm (OR 5.09; P = 0.003), posterior leaflet height >15 mm (OR 3.80; P = 0.012) and basal septal diameter ≥ 15 mm (OR 3.63; P = 0.039). CONCLUSIONS The risk for SAM can be predicted using intraoperative transoesophageal echocardiography. The combination of a smaller left ventricle, tall posterior leaflet, narrow aorto-mitral angle and enlarged basal septum significantly increases the risk for SAM. Knowing these parameters prior to valve repair can assist the surgeon in adjusting their repair technique to minimize the risk.

Management of systolic anterior motion after mitral valve repair: An algorithm

OBJECTIVE To evaluate the effectiveness and outcomes of an intraoperative and postoperative algorithm for managing systolic anterior motion (SAM) after mitral valve repair (MVRr). METHODS All consecutive patients who underwent MVRr for degenerative disease from January 2002 to June 2011 were included, with the data collected retrospectively. Patients who underwent MVRr for primary SAM were excluded from the study. Patients who developed SAM after the repair were systematically treated according to the algorithm. The intraoperative algorithm first involved medical management techniques, followed by surgical correction for significant SAM (mild or greater mitral regurgitation, left ventricular outflow tract gradient > 50 mm Hg). The postoperative algorithm focused on medical management and symptoms to guide the treatment decisions. RESULTS The overall in-hospital incidence of SAM was 6.6% (52/785). In 41 patients, SAM was identified in the operating room, and in 11 patients, it was found postoperatively on the predischarge echocardiogram. Of the 41 patients with intraoperative SAM, 35 (85.4%) had resolution with medical management and 6 (14.6%) required surgical repeat repair while in the operating room. No patient required mitral valve replacement for persistent SAM. Postoperatively, 11 new cases were identified, and 7 cases of resolved intraoperative SAM recurred. These postoperative cases of SAM were managed according to the postoperative SAM algorithm. At last follow-up, 17 (94.4%) of 18 patients had resolution of SAM and 1 (5.6%) patient had mild SAM (less than mild mitral regurgitation, peak left ventricular outflow tract gradient < 50 mm Hg) and were asymptomatic. No patients with postoperative SAM required reoperation after their initial surgery. The median echocardiographic follow-up was 1.3 years. During follow-up, 1 early death (noncardiac) and 2 late deaths (1 noncardiac, 1 of unknown etiology) occurred. CONCLUSIONS SAM is a relatively frequent complication after MVRr and can occur intraoperatively or postoperatively. A systematic approach addressing perioperative SAM after MVRr yields excellent mid-term results.

Trends in Infective Endocarditis in California and New York State, 1998-2013

Importance Prophylaxis and treatment guidelines for infective endocarditis have changed substantially over the past decade. In the United States, few population-based studies have explored the contemporary epidemiology and outcomes of endocarditis. Objective To quantify trends in the incidence and etiologies of infective endocarditis in the United States. Design, Setting, and Participants Retrospective population epidemiology study of patients hospitalized with a first episode of endocarditis identified from mandatory state databases in California and New York State between January 1, 1998, and December 31, 2013. Exposure Infective endocarditis. Main Outcomes and Measures Outcomes were crude and standardized incidence of endocarditis and trends in patient characteristics and disease etiology. Trends in acquisition mode, organism, and mortality were analyzed. Results Among 75 829 patients with first episodes of endocarditis (mean [SD] age, 62.3 [18.9] years; 59.1% male), the standardized annual incidence was stable between 7.6 (95% CI, 7.4 to 7.9) and 7.8 (95% CI, 7.6 to 8.0) cases per 100 000 persons (annual percentage change [APC], −0.06%; 95% CI, −0.3% to 0.2%; P = .59). From 1998 through 2013, the proportion of patients with native-valve endocarditis decreased (from 74.5% to 68.4%; APC, −0.7%; 95% CI, −0.9% to −0.5%; P < .001). Prosthetic-valve endocarditis increased (from 12.0% to 13.8%; APC, 1.3%; 95% CI, 0.8% to 1.7%; P < .001), and cardiac device–related endocarditis increased (from 1.3% to 4.1%; APC, 8.8%; 95% CI, 7.8% to 9.9%; P < .001). The proportion of patients with health care–associated nosocomial endocarditis decreased (from 17.7% to 15.3%; APC, −1.0%; 95% CI, −1.4% to −0.7%; P < .001). The proportion of patients with health care–associated nonnosocomial endocarditis increased (from 32.1% to 35.9%; APC, 0.8%; 95% CI, 0.5% to 1.1%; P < .001). The incidence of oral streptococcal endocarditis did not increase (unadjusted: APC, −0.1%; 95% CI, −0.8% to 0.6%; P = .77; adjusted: APC, −1.3%; 95% CI, −1.8% to −0.7%; P < .001). Crude 90-day mortality was unchanged (from 23.9% to 24.2%; APC, −0.3%; 95% CI, −1.0% to 0.4%; P = .44); adjusted risk of 90-day mortality decreased (adjusted hazard ratio per year, 0.982; 95% CI, 0.978 to 0.986; P < .001). Conclusions and Relevance In California and New York State, the overall standardized incidence of infective endocarditis was stable from 1998 through 2013, with changes in patient characteristics and etiology over this time.

Survival and Outcomes Following Bioprosthetic vs Mechanical Mitral Valve Replacement in Patients Aged 50 to 69 Years

IMPORTANCE In nonelderly patients with mitral disease requiring valve replacement, deciding between bioprosthetic and mechanical prosthetic valves is challenging because long-term survival and morbidity are not well defined. OBJECTIVE To quantify survival and major morbidity after mitral valve replacement in patients aged 50 to 69 years. DESIGN, SETTING, AND PARTICIPANTS Retrospective cohort analysis of 3433 patients (aged 50-69 years) who underwent primary, isolated mitral valve replacement in New York State hospitals from 1997-2007. Follow-up ended November 30, 2013; median duration was 8.2 years (range, 0-16.8 years). Propensity score matching for 19 baseline characteristics yielded 664 patient pairs. EXPOSURES Bioprosthetic vs mechanical prosthetic mitral valve replacement. MAIN OUTCOMES AND MEASURES All-cause mortality, stroke, reoperation, and major bleeding events. RESULTS No survival difference was observed between use of mechanical prosthetic and bioprosthetic mitral valves in patients aged 50 to 69 years matched by propensity score or in a subgroup analysis of age by decade. Among patients matched by propensity score, the incidences of stroke and bleeding events were both significantly higher in those who received mechanical prosthetic mitral valves compared with those who received bioprosthetic mitral valves; however, the incidence of reoperation was lower in the mechanical prosthesis group compared with the bioprosthesis group. [table: see text] CONCLUSIONS AND RELEVANCE Among patients aged 50 to 69 years undergoing mitral valve replacement in New York State, there was no significant survival difference at 15 years in patients matched by propensity score who underwent mechanical prosthetic vs bioprosthetic mitral valve replacement. Mechanical prosthetic valves were associated with lower risk of reoperation but greater risk of bleeding and stroke. Even though these findings suggest bioprosthetic mitral valve replacement may be a reasonable alternative to mechanical prosthetic valve replacement in patients aged 50 to 69 years, the 15-year follow-up was insufficient to fully assess lifetime risks, particularly of reoperation.

Operative mortality and stroke after on-pump vs off-pump surgery in high-risk patients: an analysis of 83 914 coronary bypass operations

OBJECTIVES The objective of this study was to compare the early outcomes of off-pump and on-pump surgeries in high-risk patient groups. METHODS The outcomes of 83,914 high-risk patients undergoing off-pump or on-pump isolated coronary bypass surgery identified from the Nationwide Inpatient Sample from 2005 to 2010 were compared using propensity analysis. RESULTS Off-pump surgery was associated with a significant reduction in stroke rates compared with on-pump surgery in propensity-matched patients ≥ 80 years (odds ratio [OR] 0.70, 95% confidence interval [CI] 0.52-0.93, P = 0.02), those with peripheral vascular disease (OR 0.53, 95% CI 0.36-0.77, P = 0.001) and those with aortic atherosclerosis (OR 0.30, 95% CI 0.13-0.72, P = 0.007). In these high-risk subgroups, off-pump surgery was associated with an absolute risk reduction in stroke rates of 0.5, 0.5 and 1.2%, respectively: the minimum number needed to treat to prevent one stroke is 200 patients. There was no significant difference in in-hospital mortality or the incidence of postoperative renal failure or respiratory failure between off-pump and on-pump surgeries in these patient subgroups, or in patients with preoperative renal failure, or chronic obstructive airways disease. CONCLUSIONS High-risk patients undergoing coronary artery bypass surgery gain a short-term benefit from off-pump approaches due to a small absolute reduction in the risk of postoperative stroke.

Incidence and Outcomes of Heparin-Induced Thrombocytopenia in Patients Undergoing Cardiac Surgery in North America: An Analysis of the Nationwide Inpatient Sample

OBJECTIVES The objective of this study was to quantify the impact of heparin-induced thrombocytopenia (HIT) on outcomes after cardiac surgery. DESIGN Retrospective analysis of national database. SETTING United States hospitals. PARTICIPANTS Patients identified from 186,771 discharge records undergoing cardiac surgery from the Nationwide Inpatient Sample between 2009 and 2010. INTERVENTIONS None. MEASUREMENTS AND MAIN RESULTS Heparin-induced thrombocytopenia was diagnosed in 506 (0.3%), and secondary thrombocytopenia was diagnosed in 16,809 (8.7%). Operative mortality was 11.1% in patients with HIT compared to 4.5% for patients without thrombocytopenia (p<0.001) and 4.0% for patients with a diagnosis of secondary thrombocytopenia (p<0.001). After adjusting for baseline patient comorbidity, the strongest independent predictors of HIT in patients undergoing cardiac surgery were female gender (OR 1.4, 95% confidence interval [CI] 1.28-1.48), congestive heart failure (OR 1.8, 95% CI 1.71-1.98), cardiac insufficiency (OR 2.2, 95% CI 1.97-2.39), atrial fibrillation (OR 1.4, 95% CI 1.30-1.51), liver disease (OR 2.2, 95% CI 1.96-2.50), and chronic renal failure (OR 1.4, 95% CI 1.30-1.51). HIT was associated with significantly increased risk of major adverse postoperative outcomes including death (OR 1.5, 95% CI 1.3-1.7), stroke (OR 2.4, 95% CI 1.9-3.1), amputation (OR 7.46, 95% CI 4.0-14.0), and acute renal failure (OR 2.3, 95% CI 2.1-2.5), respiratory failure (OR 1.9, 95% CI 1.8-2.1), and need for tracheostomy (OR 2.7, 95% CI 2.3-3.1). CONCLUSIONS Heparin-induced thrombocytopenia is associated with a 50% increase in early mortality, and most patients with this diagnosis experience major postoperative morbidity or functional deficits.

Right Ventricular Failure After Cardiac Surgery: Management Strategies

Right ventricular failure after cardiac surgery is a difficult clinical dilemma. We review the physiology of right ventricular failure in addition to current management strategies to address it.

Initial experience with routine less invasive implantation of HeartMate II left ventricular assist device without median sternotomy

OBJECTIVES Standard implantation of HeartMate II (HMII) left ventricular assist device requires an extended median sternotomy; this incision, while generally well tolerated, may add morbidity in critically ill debilitated patients. We recently adopted a sternum sparing technique for routine HMII implants using a left subcostal incision to create a pocket and access the left ventricular apex, and a right minithoracotomy to access the ascending aorta. METHODS Retrospective analysis of 40 consecutive patients (M:F 32 : 8; age range 48-77 years; Interagency Registry for Mechanically Assisted Circulatory Support 1 = 8; 2 = 10; 3 or 4 = 22) who underwent implantation of HMII using a non-sternotomy approach in a single institution. RESULTS HMII insertion was completed with the less invasive technique in all cases with no conversions to full sternotomy. There were no reoperations for bleeding and 70% of patients did not have any intraoperative blood product transfusion. No patient required right ventricular assist device support. Majority of patients (80%) were extubated by postoperative day 1. There were no wound, mediastinal or pocket infections. One patient suffered a new perioperative stroke. Median postoperative hospital stay was 19 days. Operative mortality was 7.5% and 12-month actuarial survival was 86 ± 6%. CONCLUSIONS Primary HMII implantation without median sternotomy is feasible and can be safely, effectively and routinely applied, using our less invasive approach. Further investigation is necessary to determine whether the non-invasive technique contributed to the low incidence of bleeding, blood transfusion, respiratory morbidity and right ventricular failure seen in this study.