Outcomes of minimally invasive mitral valve surgery in patients with an ejection fraction of 35% or less.

OBJECTIVE: We evaluated the outcomes of minimally invasive mitral valve surgery via a right anterior thoracotomy approach in patients with isolated severe mitral regurgitation and severely reduced left ventricular systolic function. METHODS: We retrospectively reviewed all minimally invasive mitral valve surgeries for mitral regurgitation in patients with an ejection fraction of 35% or less performed at our institution between December 2008 and June 2011. The operative times, lengths of stay, postoperative complications, and mortality were analyzed. RESULTS: We identified a total of 71 patients with severe mitral regurgitation and an ejection fraction of 35% or less who underwent minimally invasive mitral valve surgery. The mean ± SD age was 67 ± 10 years, and 44 of the patients were men (62%). The mean ± SD left ventricular ejection fraction was 27% ± 6%, and 28 patients (39%) had previous heart surgery. The median aortic cross-clamp and cardiopulmonary bypass times were 62 [interquartile range (IQR), 50-80) and 98 minutes (IQR, 92-124), respectively. There was no mitral regurgitation noted in any patient on postoperative transesophageal echocardiogram. The median intensive care unit length of stay was 51 hours (IQR, 42-86), and the median postoperative length of stay was 6 days (IQR, 5-9). CONCLUSIONS: Minimally invasive mitral valve surgery for severe functional mitral regurgitation in patients with severe left ventricular dysfunction can be performed with a low morbidity and mortality.

Clinical predictors of prosthesis-patient mismatch after aortic valve replacement for aortic stenosis.

OBJECTIVE: We sought to ascertain predictors of Patient Prosthesis Mismatch, an independent predictor of mortality, in patients with aortic stenosis using bioprosthetic valves. METHOD: We analyzed 2,107 sequential surgeries. Patient Prosthesis Mismatch was calculated using the effective orifice area of the prosthesis divided by the patient's body surface area. We defined nonsignificant, moderate, and severe Patient Prosthesis Mismatch as effective orifice area indexes of .0.85 cm(2)/m, 0.85-0.66 cm(2)/m(2), and <0.65 cm(2)/m(2), respectively. RESULTS: A total of 311 bioprosthetic patients were identified. The incidence of nonsignificant, moderate, and severe Patient Prosthesis Mismatch was 41%, 42, and 16%, respectively. Severe Patient Prosthesis Mismatch was significantly more prevalent in females (82%). In severe Patient Prosthesis Mismatch, the perfusion and the crossclamp times were considerably lower when compared with nonsignificant Patient Prosthesis Mismatch and moderate Patient Prosthesis Mismatch. Patients with severe Patient Prosthesis Mismatch had a significantly higher likelihood of spending time in the intensive care unit and a significantly longer length of stay in the hospital. Body surface area was not different in severe Patient Prosthesis Mismatch when compared with nonsignificant Patient Prosthesis Mismatch. In-hospital mortality in patients with nonsignificant, moderate, and severe Patient Prosthesis Mismatch was 2.3%, 6.1%, and 8%, respectively. Minimally invasive surgery was significantly associated with moderate Patient Prosthesis Mismatch in 49% of the patients, but not with severe Patient Prosthesis Mismatch. CONCLUSION: Severe Patient Prosthesis Mismatch is more common in females, but not in those with minimal available body surface area. Though operative times were shorter in these patients, intensive care unit and hospital lengths of stay were longer. Surgeons and cardiologists should be cognizant of these clinical predictors and complications prior to valve surgery.

Clinical predictors of prosthesis-patient mismatch after aortic valve replacement for aortic stenosis

OBJECTIVE: We sought to ascertain predictors of Patient Prosthesis Mismatch, an independent predictor of mortality, in patients with aortic stenosis using bioprosthetic valves. METHOD: We analyzed 2,107 sequential surgeries. Patient Prosthesis Mismatch was calculated using the effective orifice area of the prosthesis divided by the patient's body surface area. We defined nonsignificant, moderate, and severe Patient Prosthesis Mismatch as effective orifice area indexes of .0.85 cm²/m, 0.85-0.66 cm²/m², and <0.65 cm²/m², respectively. RESULTS: A total of 311 bioprosthetic patients were identified. The incidence of nonsignificant, moderate, and severe Patient Prosthesis Mismatch was 41 percent, 42, and 16 percent, respectively. Severe Patient Prosthesis Mismatch was significantly more prevalent in females (82 percent). In severe Patient Prosthesis Mismatch, the perfusion and the crossclamp times were considerably lower when compared with nonsignificant Patient Prosthesis Mismatch and moderate Patient Prosthesis Mismatch. Patients with severe Patient Prosthesis Mismatch had a significantly higher likelihood of spending time in the intensive care unit and a significantly longer length of stay in the hospital. Body surface area was not different in severe Patient Prosthesis Mismatch when compared with nonsignificant Patient Prosthesis Mismatch. In-hospital mortality in patients with nonsignificant, moderate, and severe Patient Prosthesis Mismatch was 2.3 percent, 6.1 percent, and 8 percent, respectively. Minimally invasive surgery was significantly associated with moderate Patient Prosthesis Mismatch in 49 percent of the patients, but not with severe Patient Prosthesis Mismatch. CONCLUSION: Severe Patient Prosthesis Mismatch is more common in females, but not in those with minimal available body surface area. Though operative times were shorter in these patients, intensive care unit and hospital lengths of stay were longer. Surgeons and cardiologists should be cognizant of these clinical predictors and complications prior to valve surgery.

The influence of atrial and ventricular pacing on the incidence of atrial fibrillation: a meta-analysis.

BACKGROUND: The effect of atrial pacing on the incidence of atrial fibrillation (AF) is unknown. Furthermore, the threshold of ventricular pacing that is associated with a higher incidence of AF has yet to be determined. Thus, we set out to determine the optimal pacing modality in patients with sinus node dysfunction (SND) for the prevention of AF. METHODS: Individual patient data from four contemporary pacemaker studies were gathered and analyzed. Since AF would inherently lead to a reduction in atrial pacing, percent atrial and ventricular pacing (%AP and %VP) were determined at the first follow-up visit and then used as a surrogate for all endpoints. Patients with >5 minutes of AF at the first visit were excluded. The primary endpoint was defined as 7 consecutive days of AF. RESULTS: A total of 1,507 patients were included. During a mean follow-up of 14.3 ± 8.7 months, 77 patients developed AF (annual rate of 4.3%). The incidence of AF in the first (0-32%), second (32-66%), third (66-89%), and fourth (89-100%) quartiles of %AP was 1.3%, 5.3%, 5.8%, and 8.0%, respectively (P < 0.001). A multivariable analysis found that pacing above the first quartile was associated with a relative risk of 2.93 (95% confidence interval 1.16-7.39, P = 0.023). The grouping of %VP into first (0-2%), second (2-7%), third (7-84%), and fourth (84-100%) quartiles yielded an AF incidence of 2.4%, 3.4%, 6.6%, and 8.0%, respectively (P = 0.001). CONCLUSION: We demonstrated that in patients with SND both atrial and ventricular pacing are associated with a higher incidence of AF.