Minimally invasive mitral valve surgery in high-risk patients: operating outside the boxplot

Sex-specific differences and postoperative outcomes of minimally invasive and sternotomy valve surgery

OBJECTIVES

Female sex is an established risk factor for postoperative complications after heart surgery, but the influence of sex on outcomes after minimally invasive cardiac surgery (MICS) for valvular replacement/repair remains controversial. We examined whether the role of sex as a risk factor varies by surgical approach [MICS vs conventional sternotomy (ST)] and further assessed outcomes among female patients including in-hospital mortality and postoperative complications by surgical approach.

METHODS

We analysed data from a multicentre registry for patients who underwent isolated aortic valve and mitral surgery with MICS or ST. The primary outcome was in-hospital mortality. Propensity score matching was used to minimize between-group differences.

RESULTS

Among the 15 155 patients included in the study, 7674 underwent MICS (50.6%). Female sex was equally distributed in the MICS and ST groups (47.3% vs 47.6%, respectively). Risk for surgery was higher in the ST group than in the MICS group {EuroSCORE II: 4.0 [standard deviation (SD): 6.8] vs 3.7 [SD: 6.4]; P = 0.005}, including among female patients only [ST vs MICS 4.6 (SD: 6.9) vs 4.2 (SD: 6.3); P = 0.04]. Mortality did not significantly vary by procedure among women [MICS vs ST, 2.4% vs 2.8%; hazard ratio 1.09, 95% confidence interval 0.71-1.73; P (surgical approach × sex) = 0.51]. The results also did not vary after adjusting for confounders.

CONCLUSIONS

Female sex was associated with higher mortality in patients undergoing valve surgery, regardless of surgical approach. In female patients, MICS did not provide any benefits over ST in terms of in-hospital deaths or postoperative complications.

SUBJECT COLLECTION

117, 125.

The Effect of Minimally Invasive Surgery and Sternotomy on Physical Activity and Quality of Life

AIM

The aim of this study was to compare minimally invasive surgery (MI) and median sternotomy (MS) in terms of post-procedure health-related quality of life (HRQoL) and functional outcome.

METHOD

We conducted a multicentre prospective cohort study that enrolled patients from January 2015 until February 2017. Combined cardiac procedures were performed with MS and isolated valve procedures with either MS or MI, depending on patient preference and surgeon experience. HRQoL was measured using the five-level version of the EQ-5D (EQ-5D-5L) and physical activity before and after surgery was evaluated using a wearable accelerometer. Activity patterns and intensity recorded by the accelerometer in each period were classified as "sedentary", "light physical activity", "moderate physical activity", and "vigorous physical activity" for each patient. We also conducted a sub-analysis of frail patients in each group, as identified by the Reported Edmonton Frail Scale (>10 points). Patients were followed for 1 year.

RESULTS

The study included 100 consecutive patients who underwent MI (n=50) or MS (n=50) during the study period. Patients in the MI group showed a faster recovery of physical activity in the immediate postoperative period and superior HRQoL in the first 3 months (both p<0.001) versus the MS group. Differences between the MI and MS group were indistinguishable over a longer follow-up. A similar correlation was observed in the frailty subanalysis. Overall, the MS group had a higher cumulative incidence of events than the MI group (p<0.001).

CONCLUSIONS

Compared to conventional MS, MI was associated with better HRQoL and early functional outcome, even in frail patients.

A Trial of Two Anesthetic Regimes for Minimally Invasive Mitral Valve Repair

OBJECTIVE

Minimally invasive mitral valve repair may be associated with prolonged cardioplegic arrest times and ischemic reperfusion injury. Intravenous (propofol) and volatile (sevoflurane) anesthesia are used routinely during cardiac surgery and are thought to provide cardioprotection; however, the individual contribution of each regimen to cardioprotection is unknown. Therefore, the authors sought to compare the cardioprotective effects of propofol and sevoflurane anesthesia in patients undergoing minimally invasive mitral valve repair.

DESIGN

A single-center single-blind randomized controlled trial.

SETTING

A specialized regional cardiac surgery center in Italy.

PARTICIPANTS

The study enrolled 62 adults undergoing elective isolated minimally invasive mitral valve repair for degenerative disease. Exclusion criteria included secondary mitral regurgitation, previously treated coronary artery disease, diabetes mellitus, chronic renal failure requiring dialysis, atrial fibrillation, and documented allergy to either propofol or sevoflurane.

INTERVENTIONS

All patients received video-assisted minimally invasive right minithoracotomy. Patients were randomized to receive propofol or sevoflurane anesthesia in a 1:1 ratio.

MEASUREMENTS AND MAIN RESULTS

Cardiac troponin I release was measured over the first 72 hours postoperatively. Operative, cross-clamp, and total bypass times were similar between groups. Cardiac troponin I release was reduced nonsignificantly in the propofol group (p = 0.62), and peak troponin I release was correlated with cross-clamp time in both groups. There were no differences in terms of intraoperative lactate release and blood pH between groups.

CONCLUSION

Propofol and sevoflurane anesthesia were associated with similar degrees of myocardial injury, indicating comparable cardioprotection. Myocardial injury was related directly to the duration of cardioplegic arrest.

Predictors of survival in octogenarians after mitral valve surgery for degenerative disease: The Mitral Surgery in Octogenarians study

OBJECTIVES

An increasing number of octogenarians are referred to undergo mitral valve surgery for degenerative disease, and percutaneous approaches are being increasingly used in this subgroup of patients. We sought to determine the survival and its predictors after Mitral Valve Surgery in Octogenarians (MiSO) in a multicenter UK study of high-volume specialized centers.

METHODS

Pooled data from 3 centers were collected retrospectively. To identify the predictors of short-term composite outcome of 30 days mortality, acute kidney injury, and cerebrovascular accident, a multivariable logistic regression model was developed. Multiple Cox regression analysis was performed for late mortality. Kaplan-Meier curves were generated for long-term survival in various subsets of patients. Receiver operating characteristic analysis was done to determine the predictive power of the logistic European System for Cardiac Operative Risk Evaluation.

RESULTS

A total of 247 patients were included in the study. The median follow-up was 2.9 years (minimum 0, maximum 14 years). A total of 150 patients (60.7%) underwent mitral valve repair, and 97 patients (39.3%) underwent mitral valve replacement. Apart from redo cardiac surgery (mitral valve repair 6 [4%] vs mitral valve replacement 11 [11.3%], P = .04) and preoperative atrial fibrillation (mitral valve repair 79 [52.6%] vs mitral valve replacement 34 [35.1%], P < .01), there was no significant difference in terms of any other preoperative characteristics between the 2 groups. Patient operative risk, as estimated by logistic European System for Cardiac Operative Risk Evaluation, was lower in the mitral valve repair group (10.2 ± 11.8 vs 13.7 ± 15.2 in mitral valve replacement; P = .07). No difference was found between groups for duration of cardiopulmonary bypass and aortic crossclamp times. The 30-day mortality for the whole cohort was 13.8% (mitral valve repair 4.7% vs mitral valve replacement 18.6%; P < .01). No differences were found in terms of postoperative cerebrovascular accident (2% vs 3.1%; P = .9), acute kidney injury requiring dialysis (6.7% vs 13.4%; P = .12), and superficial or deep sternal wound infection (10% vs 16.5%, P = .17; 2% vs 3.1%, P = .67, respectively). The final multiple regression model for short-term composite outcome included previous cardiac surgery (odds ratio [OR], 4.47; 95% confidence interval [CI], 1.37-17.46; P = .02), intra-aortic balloon pump use (OR, 4.77; 95% CI, 1.67-15.79; P < .01), and mitral valve replacement (OR, 7.7; 95% CI, 4.04-14.9; P < .01). Overall survival for the entire cohort at 1, 5, and 10 years was 82.4%, 63.7%, and 45.5% (mitral valve repair vs mitral valve replacement: 89.9% vs 70.7% at 1 year, 69.6% vs 54% at 5 years, and 51.8% vs 35.5% at 10 years; P = .0005). Cox proportional hazard model results showed mitral valve replacement (hazard ratio, 1.88; 95% CI, 1.22-2.89; P < .01) and intra-aortic balloon pump use (hazard ratio, 2.54; 95% CI, 1.26-5.13; P < .01) to be independent predictor factors affecting long-term survival. Logistic European System for Cardiac Operative Risk Evaluation did not perform well in predicting early mortality (area under the curve, 0.57%).

CONCLUSIONS

In octogenarians, mitral valve repair for degenerative disease is associated with good survival and remains the gold standard, whereas mitral valve replacement is still associated with significant mortality. Logistic European System for Cardiac Operative Risk Evaluation was unable to predict early mortality in our cohort of patients. Larger international multicenter registries are required to optimize the decision-making process in such a high-risk subgroup.