Gonçalo F. Coutinho

Aortic root enlargement does not increase the surgical risk and short-term patient outcome?

OBJECTIVE To analyze the short-term outcome of aortic root enlargement (ARE) using death and adverse events as end points. METHODS From January 1999 through December 2009, 3339 patients were subjected to aortic valve replacement (AVR). A total of 678 were considered to have small aortic roots (SARs) in which an aortic prosthesis size 21 mm or smaller was implanted. ARE using a bovine pericardial patch was performed in another 218 patients, who constitute the study population. This comprised 174 females (79.8%); the mean age was 69.4 ± 13.4 years (8-87, median 74 years), the body surface area (BSA) was 1.59 ± 0.15m² and the body mass index (BMI) 25.77 ± 3.16 k gm⁻², and 192 (88.5%) were in New York Heart Association (NYHA) II-III. Preoperative echocardiography revealed significant left ventricular (LV) dysfunction in 17 patients (8%), a mean aortic valve area of 0.57 ± 0.27 cm², and a mean gradient of 62.51 ± 21.25 mm Hg. A septal myectomy was performed in 129 subjects (59.2%), and other associated procedures, mostly coronary artery bypass grafting (CABG), in 60 (27.5%). Bioprostheses were implanted in 161 patients (73.9%). The mean valve size was 21.9 ± 1.0 (21-25). The mean extracorporeal circulation (ECC) and aortic clamping times were 82.8 ± 19.8 min and 56.8 ± 12.5 min, respectively. RESULTS Hospital mortality was 0.9% (n=2) for ARE as compared with 0.6% (n=4) for the SAR group (p=0.8). Inotropic support was required in only 13 (5.9%) patients and the first 24-h chest drainage was 336.2 ± 202 ml. Other complications included pacemaker implantation (7.8%), acute renal failure (10.6%), respiratory (4.1%), and CVA/transient ischemic attack (CVA/TIA) (3.2%). Postoperative echocardiographic evaluation showed a significant decrease in peak and mean aortic gradients (23.7 ± 9.5 and 14 ± 6.2 mm Hg, respectively, p<0.0001). The mean indexed effective orifice area (iEOA) was 0.92 ± 0.01 cm² m⁻² (vs 0.84±0.07 cm² m⁻², in SAR, p<0.0001). Only 11% of patients (n=24) with ARE exhibited moderate patient-prosthesis mismatch (PPM) and none had severe PPM. Mean hospital stay was 9.7 ± 9.29 days (median 7 days). CONCLUSIONS With the growing number of patients with degenerative aortic valve pathology, mainly an older population, sometimes with calcified and fragile aortic wall, the issue of dealing with an SAR poses the dilemma of whether to implant a smaller prosthesis and admit some degree of PPM, or to enlarge the aortic root. This study demonstrates that the latter can be done in a safe and reproducible manner.

Management of moderate secondary mitral regurgitation at the time of aortic valve surgery

OBJECTIVES To define the impact of surgical strategy [concomitant mitral valve surgery or isolated aortic valve replacement (AVR)] in patients with moderate secondary mitral regurgitation (MR) at the time of AVR. METHODS From January 1999 to December 2009, 3339 patients underwent AVR of whom 255 had secondary MR >2+ and constituted the study population. Patients were stratified into two groups, with (Group A, n = 94, 36.8%) and without concomitant mitral valve surgery (Group B, n = 161, 63.2%). Follow-up up to 12 years (1076 patient-years) was analysed for survival, valve-related events and persistent MR. Predictors of late mortality and persistent MR were further analysed. A case-match analysis [age, gender, New York Heart Association (NYHA) and left ventricular ejection fraction] was performed, excluding patients with coronary artery disease (CAD). RESULTS The mean age of the population was 67.0 ± 11.7 years, 63.5% male and 64.7% in NYHA III-IV. Group B patients were significantly older and had higher incidence of coronary disease, hypertension and mitral calcification. They also had a higher ejection fraction and transaortic gradients, and lower MR grade (mean MR: 2.8 vs 3.2) and pulmonary artery pressure. Mitral surgery consisted mainly of annuloplasty procedures (96%). Only 2 patients from the entire cohort were reoperated on/for the mitral valve. Thirty-day mortality rate was 0.3%. There was no difference in long-term survival and valve-related complications, even after case-matched analysis. CAD, history of cerebrovascular accident, permanent atrial fibrillation, renal failure and persistence of MR emerged as independent predictors of late mortality (P < 0.05). MR improved in 67.4% of patients from Group B against 82.3% from Group A (P = 0.011). Atrial fibrillation (AF) and higher MR grade at discharge were the only independent predictors for persistent MR (P < 0.05). Patients with persistent MR early after AVR had decreased late survival (hazard ratio: 4.9, P = 0.001). CONCLUSIONS Secondary MR improves after AVR even without mitral surgery. Concomitant mitral surgery was significantly associated with greater improvement of postoperative MR, but had no significant impact on survival. However, patients who did not improve immediately after AVR had compromised survival. Patients in AF should have mitral valve repair at the time of surgery.

Diagnostic value of surgical lung biopsy: comparison with clinical and radiological diagnosis

OBJECTIVE To determine overall and disease-related accuracy of the clinical/imagiological evaluation for pulmonary infiltrates of unknown aetiology, compared with the pathological result of the surgical lung biopsy (SLB) and to evaluate the need for the latter in this setting. METHODS We conducted a retrospective review of the experiences of SLB in 366 consecutive patients during the past 5 years. The presumptive diagnosis was based on clinical, imagiological and non-invasive or minimally invasive diagnostic procedures and compared with the gold standard of histological diagnosis by SLB. We considered five major pathological groups: diffuse parenchymal lung disease (DPLD), primitive neoplasms, metastases, infectious disease and other lesions. Patients with previous histological diagnosis were excluded. RESULTS In 56.0% of patients (n=205) clinical evaluation reached a correct diagnosis, in 42.6% a new diagnosis was established (n=156) by the SLB, which was inconclusive in 1.4% (n=5). The pre-test probability for each disease was 85% for DPLD, 75% for infectious disease, 64% for primitive neoplasms and 60% for metastases. Overall sensitivity, specificity, positive and negative predictive values for the clinical/radiological diagnosis were 70%, 90%, 62% and 92%, respectively. For DPLD: 67%, 90%, 76% and 85%; primitive neoplasms: 47%, 90%, 46% and 90%; metastases: 99%, 79%, 60% and 99%; infectious disease 38%, 98%, 53% and 96%. CONCLUSIONS Despite a high sensitivity and specificity of the clinical and imagiological diagnosis, the positive predictive value was low, particularly in the malignancy group. SLB should be performed in pulmonary infiltrates of unknown aetiology because the clinical/imagiological assessment missed and/or misdiagnosed an important number of patients.

Long-term follow-up of asymptomatic or mildly symptomatic patients with severe degenerative mitral regurgitation and preserved left ventricular function

OBJECTIVES The timing for mitral valve surgery in asymptomatic patients with severe mitral regurgitation and preserved left ventricular function remains controversial. We analyzed the immediate and long-term outcomes of these patients after surgery. METHODS From January 1992 to December 2012, 382 consecutive patients with severe chronic degenerative mitral regurgitation, with no or mild symptoms, and preserved left ventricular function (ejection fraction ≥ 60%) were submitted to surgery and followed for up to 22 years (3209 patient-years). Patients with associated surgeries, other than tricuspid valve repair, were excluded. Cox proportional-hazard survival analysis was performed to determine predictors of late mortality and mitral reoperation. Subgroup analysis involved patients with atrial fibrillation or pulmonary hypertension. RESULTS Mitral valvuloplasty was performed in 98.2% of cases. Thirty-day mortality was 0.8%. Overall survival at 5, 10, and 20 years was 96.3% ± 1.0%, 89.7% ± 2.0%, and 72.4% ± 5.8%, respectively, and similar to the expected age- and gender-adjusted general population. Patients with atrial fibrillation/pulmonary hypertension had a 2-fold risk of late mortality compared with the remaining patients (hazard ratio, 2.54; 95% confidence interval, 1.17-4.80; P = .018). Benefit was age-dependent only in younger patients (<65 years; P = .016). Patients with atrial fibrillation/pulmonary hypertension (hazard ratio, 4.20, confidence interval, 1.10-11.20; P = .037) and patients with chordal shortening were at increased risk for reoperation, whereas patients with P2 prolapse (hazard ratio, 0.06; confidence interval, 0.008-0.51; P = .037) and patients with myxomatous valves (hazard ratio, 0.072; confidence interval, 0.008-0.624; P = .017) were at decreased risk. CONCLUSIONS Mitral valve repair can be achieved in the majority of patients with low mortality (<1%) and excellent long-term survival. Patients with atrial fibrillation/pulmonary hypertension had compromised long-term survival, particularly younger patients (aged <65 years), and are at increased risk of mitral reoperation.

Long-term follow-up of elderly patients subjected to aortic valve replacement with mechanical prostheses.

We propose to analyse the long-term follow-up in patients older than 65 years of age who received a mechanical valve in the aortic position, using death and prosthetic-related complications as endpoints. From April 1988 to December 1995, 144 consecutive patients 65-75 years of age (mean 67.7+/-2.5) were enrolled. Total duration of follow-up was 1663 patient-years (median 13.0 years) and was complete for 99% of the patients. Thirty-day mortality was 1.4% (n=2). At the end of the study, 77 patients (53.8%) were alive, with ages ranging from 77 to 91 years (mean 82.1+/-3.2 years). The overall 5-, 10- and 15-year actuarial survival was 87.4%+/-3.0, 67.7%+/-4.3 and 58.5%+/-4.5, respectively. Freedom from stroke was 93.3+/-3.1%, 84.6+/-3.3% and 71.7+/-4.5%, respectively, after identical periods. Freedom from major bleeding was 97.2+/-1.1%, 90.4+/-3.5% and 86.4+/-4.0%, respectively. Freedom from endocarditis was 95.7+/-2.3%, 95.0+/-2.1% and 94.4+/-2.5%, respectively, and freedom from reoperation was 98.0+/-1.2%, 97.6+/-1.3%, 96.9+/-2.4% and 96.4+/-2.6%, respectively. Freedom from major valve-related events was 87.7+/-2.6%, 73.9+/-3.4% and 61.5+/-4.6%, respectively. Nearly two-thirds of the patients were alive and free from major adverse valve-related events. Hence, we consider implantation of a mechanical prosthesis in elderly patients safe and appropriate, but the choice must be tailored for each specific patient.

Negative impact of atrial fibrillation and pulmonary hypertension after mitral valve surgery in asymptomatic patients with severe mitral regurgitation: a 20-year follow-up

OBJECTIVES The timing for mitral valve (MV) surgery in asymptomatic patients with severe mitral regurgitation (MR) and preserved left ventricular (LV) function remains controversial. We aimed at analysing the long-term outcome of asymptomatic patients with atrial fibrillation (AF) and/or pulmonary hypertension (PHT) after successful MV repair. METHODS From January 1992 to December 2012, 382 patients with severe degenerative MR, with no or mild symptoms, preserved LV function (ejection fraction > 60%) and LV systolic dimensions <45 mm were submitted to surgery and followed up for up to 22 years (3209 patient-years). Patients with associated surgeries, other than tricuspid repair, were excluded. Patients with AF and/or PHT (Group A; n = 106, 24.4%) were compared with patients without these comorbidities (Group B; n = 276, 63.6%). Propensity-score matching (for preoperative variables) was performed obtaining 102 patients in each arm. Survival and event-free survival [major cardiac and cerebrovascular events (MACCEs); freedom from mitral reoperation and recurrent moderate and severe MR] were analysed. RESULTS MV repair was performed in 98.2% of cases and tricuspid annuloplasty in 6.9%. Overall 30-day mortality was 0.8%, not different between groups, and absent in patients with isolated posterior leaflet prolapse (n = 211). Patients with AF/PHT had worse late survival by comparison with Group B patients (67.0 ± 7.4 vs 86.5 ± 3.9% at 15 years, P < 0.001), survival free from MACCE (52.7 ± 8.7 vs 74.5 ± 5.0%, P < 0.001), from recurrent moderate and severe MR (65.1 ± 10.3 vs 87.0 ± 3.8%, P = 0.002) and from mitral reoperation during the follow-up (87.3 ± 6.3 vs 94.2 ± 2.7%, P = 0.04). These differences were confirmed in the propensity score-matched population. Patients from Group A also displayed a lesser degree of reverse remodelling. There was a significant reduction in the systolic pulmonary artery pressure (SPAP) after surgery, more pronounced in Group A patients; nonetheless, the mean SPAP at late follow-up was higher in these patients (45 vs 30 mmHg). CONCLUSIONS MV repair can be achieved in the great majority of patients with degenerative regurgitation, with low mortality (<1%). Asymptomatic or mildly symptomatic patients with severe MR, preserved LV function and AF/PHT had poorer long-term survival and event-free survival even after a successful surgery. The durability of MV repair was also compromised in these patients, which indicates that they should have been operated earlier.

Coronary artery bypass surgery without cardioplegia: hospital results in 8515 patients

OBJECTIVES Cardioplegic myocardial protection is used in most cardiac surgical procedures. However, other alternatives have proved useful. We analysed the perioperative results in a large series of patients undergoing coronary artery bypass (CABG) using cardiopulmonary bypass (CPB) and non-cardioplegic methods. METHODS From January 1992 to October 2013, 8515 consecutive patients underwent isolated CABG with CPB without cardioplegia, under hypothermic ventricular fibrillation and/or an empty beating heart. The mean age was 61.9 ± 9.5 years, 12.4% were women, 26.3% diabetic, 64% hypertensive; and 9.6% had peripheral vascular disease, 7.8% cerebrovascular disease and 54.3% previous acute myocardial infarction (AMI). One-third of patients were in Canadian Cardiovascular Society Class III/IV. Three-vessel disease was present in 76.5% of the cases and 10.9% had moderate/severe left ventricle (LV) dysfunction (ejection fraction <40%). A multivariate analysis was made of risk factors associated to in-hospital mortality and three major morbidity complications [cerebrovascular accident, mediastinitis and acute kidney injury (AKI)], as well as for prolonged hospital stay. RESULTS The mean CPB time was 58.2 ± 20.7 min. The mean number of grafts per patient was 2.7 ± 0.8 (arterial: 1.2 ± 0.5). The left internal thoracic artery (ITA) was used in 99.4% of patients and both ITAs in 23.1%. The in-hospital mortality rate was 0.7% (61 patients), inotropic support was required in 6.6% and mechanical support in 0.8, and 2.0% were re-explored for bleeding and 1.3% for sternal complications (mediastinitis, 0.8%). AKI, the majority transient, occurred in 1595 patients (18.9%). The incidence rates of stroke/transient ischemic attack (TIA) and acute myocardial infarction (AMI) were 2.6 and 2.5%, respectively, and atrial fibrillation/flutter occurred in 22.6% of cases. Age, LV dysfunction, non-elective surgery, previous cardiac surgery, peripheral vascular disease and CPB time were independent risk factors for mortality and major morbidity. The mean hospital stay was 7.2 ± 5.7 days. CONCLUSIONS Isolated CABG with CPB using non-cardioplegic methods proved very safe, with low mortality and morbidity. These methods are simple and expeditious and remain as very useful alternative techniques of myocardial preservation.

Mitral valve surgery after percutaneous mitral commissurotomy: is repair still feasible?

OBJECTIVES Due to progression of rheumatic disease, percutaneous mitral commissurotomy (PMC) is a palliative procedure. We aimed at evaluating the outcomes of patients requiring surgery for failure of PMC, focusing on the fate of the mitral valve (MV) (repair versus replacement). METHODS From January 1993 through December 2012, 61 patients with previous PMC were submitted to MV surgery. Detailed operative findings were collected from all patients and an intraoperative anatomical score was introduced to predict reparability. Time to surgery, overall survival and freedom from reoperation were analysed. RESULTS The mean time to surgery after PMC was 6.9±5.9 years and indications were restenosis in 25 patients (41%) and mitral regurgitation or mixed lesion in 36 (59%). Nine patients (14.8%) had more than one previous intervention. Intraoperative inspection of the valve revealed leaflet laceration outside the commissural area in 27 patients (44.3%). Valve repair was accomplished in 38 patients (62.3%). Pulmonary hypertension, calcification and intraoperative anatomical score were independently associated with the probability of valve replacement (OR 1.12, OR 7.03 and OR 4.49, respectively, P<0.05). There was no hospital mortality. MV area increased on average 1.6 cm2 after surgery to 2.7 cm2; 5-, 10- and 20-year survival rates were 98.1±1.9, 91±5.2 and 82.7±9.2%, respectively. The rate of freedom from mitral reoperation (for repaired cases) at 5, 10 and 15 years was 100, 95.8±4.1 and 87.8±8.5%, respectively. There was no difference in survival between repaired or replaced MVs, but the former had less valve-related events during follow-up. CONCLUSION The MV can be repaired after failed PMC, with very low complication rates and excellent long-term results. Hence, whenever possible, these patients should be sent to reference centres where repair can be successfully achieved.

Concomitant aortic and mitral surgery: to replace or repair the mitral valve?

OBJECTIVES The study objectives were to evaluate the perioperative outcomes of concomitant mitral and aortic valve surgery and to determine the influence of mitral valve repair versus replacement on survival and adverse events. METHODS The study population comprised 261 patients with a mean age of 61.3±11.2 (19-82) years; 57.5% were male, and 73% were in New York Heart Association class III or IV. Mitral valve repair was performed in 209 patients (80%), and mitral valve replacement was performed in 52 patients (20%). Follow-up was complete for 95% of the patients (1395 patient-years). We specifically examined the impact of mitral valve repair versus replacement by comparing 2 propensity-matched subgroups. RESULTS Degenerative and functional mitral regurgitation, and left ventricular dilation and dysfunction were associated with mitral valve repair (P<.05). Rheumatic disease, chronic obstructive pulmonary disease, redo surgery, mitral calcification, and atrial fibrillation were more frequently related to mitral valve replacement (P<.05). Overall 30-day mortality was 1.1% (3 patients). Overall 1-, 5-, and 8-year survival were 98.0%±2.0%, 85.9%±6.1%, and 79.8%±8.2%, respectively, for the mitral valve replacement group and 95.3%±1.5%, 87.4%±2.6%, and 75.2%±4.0%, respectively, for the mitral valve repair group (P=.906). This was confirmed by comparable survival in propensity-matched analyses. Mitral valve repair showed a survival advantage in older patients (aged ≥65 years) and patients with nonrheumatic mitral valves (P=.017 and P=.034, respectively). Bleeding events (83% vs 60%), endocarditis (97.6% vs 84.6%), and reoperation (97.6% vs 86.9%) were higher in those undergoing mitral valve replacement. Freedom from major adverse valve-related events was higher for the mitral valve repair group (P=.002). Mitral valve replacement was identified as an independent risk factor for major adverse valve-related events (hazard ratio, 1.99; P=.018). CONCLUSIONS Concomitant mitral and aortic valve surgery carries a low surgical risk. The choice of the mitral procedure did not significantly affect survival. However, mitral valve replacement was associated with an increased incidence of adverse events. Thus, valve repair, whenever feasible, is a better option.

Mitral valve repair for degenerative mitral valve disease: surgical approach, patient selection and long-term outcomes

Mitral valve repair (MVRepair) has become the procedure of choice to correct severe degenerative mitral regurgitation (MR), due to its documented superiority to valve replacement regarding long-term survival, freedom from valve-related adverse events and preservation of left ventricular (LV) function. The refinement of MVRepair techniques has rendered almost all valves (more than 95%) amenable to repair with a 15-year freedom from reoperation of 90%. The concept of ‘centres of excellence for MVRepair’ has emerged, encouraging referring doctors to select the most experienced institutions or individual surgeons to deal with the most complex cases, based on repair volume, appropriate peri-procedural imaging and data regarding expected outcomes (repair, mortality and durability of repair). Based on the good results, operating on asymptomatic patients with severe MR is now widely accepted, prophylactically avoiding the dire consequences of chronic MR, such as LV function deterioration/enlargement, and development of atrial fibrillation and pulmonary hypertension. In reference centres, where the repair rate is over 95% for all types of disease with <1% mortality, it has become standard practice in nearly 50%–60% of all patients submitted to MVRepair. Finally, recent advances in the surgical treatment with the purpose of reducing invasiveness and surgical trauma, through partial sternotomy or mini-thoracotomy (video-assisted with or without robotics), are now being increasingly performed in 20%–30% of centres, claiming comparable results to conventional surgery. In addition, transcatheter technology, particularly the MitraClip, is evolving and treading its way in the treatment of high-risk patients with severe MR, but the results are still short of ideal.