Left Atrial Appendage Occlusion during Cardiac Surgery to Prevent Stroke.

BACKGROUND: Surgical occlusion of the left atrial appendage has been hypothesized to prevent ischemic stroke in patients with atrial fibrillation, but this has not been proved. The procedure can be performed during cardiac surgery undertaken for other reasons. METHODS: We conducted a multicenter, randomized trial involving participants with atrial fibrillation and a CHA2DS2-VASc score of at least 2 (on a scale from 0 to 9, with higher scores indicating greater risk of stroke) who were scheduled to undergo cardiac surgery for another indication. The participants were randomly assigned to undergo or not undergo occlusion of the left atrial appendage during surgery; all the participants were expected to receive usual care, including oral anticoagulation, during follow-up. The primary outcome was the occurrence of ischemic stroke (including transient ischemic attack with positive neuroimaging) or systemic embolism. The participants, research personnel, and primary care physicians (other than the surgeons) were unaware of the trial-group assignments. RESULTS: The primary analysis population included 2379 participants in the occlusion group and 2391 in the no-occlusion group, with a mean age of 71 years and a mean CHA2DS2-VASc score of 4.2. The participants were followed for a mean of 3.8 years. A total of 92.1% of the participants received the assigned procedure, and at 3 years, 76.8% of the participants continued to receive oral anticoagulation. Stroke or systemic embolism occurred in 114 participants (4.8%) in the occlusion group and in 168 (7.0%) in the no-occlusion group (hazard ratio, 0.67; 95% confidence interval, 0.53 to 0.85; P = 0.001). The incidence of perioperative bleeding, heart failure, or death did not differ significantly between the trial groups. CONCLUSIONS: Among participants with atrial fibrillation who had undergone cardiac surgery, most of whom continued to receive ongoing antithrombotic therapy, the risk of ischemic stroke or systemic embolism was lower with concomitant left atrial appendage occlusion performed during the surgery than without it. (Funded by the Canadian Institutes of Health Research and others; LAAOS III ClinicalTrials.gov number, NCT01561651.).

Left ventricular assist device implantation and concomitant mitral valve surgery: A systematic review and meta-analysis.

BACKGROUND: The management of concomitant valvular lesions in patients undergoing left ventricular assist device (LVAD) implantation remains a topic of debate. This systematic review and meta-analysis aimed to evaluate the existing evidence on postoperative outcomes following LVAD implantation, with and without concomitant MV surgery. METHODS: A systematic database search was conducted as per PRISMA guidelines, of original articles comparing LVAD alone to LVAD plus concomitant MV surgery up to February 2023. The primary outcomes assessed were overall mortality and early mortality, while secondary outcomes included stroke, need for right ventricular assist device (RVAD) implantation, postoperative mitral valve regurgitation, major bleeding, and renal dysfunction. RESULTS: The meta-analysis included 10 studies comprising 32 184 patients. It revealed that concomitant MV surgery during LVAD implantation did not significantly affect overall mortality (OR:0.83; 95% CI: 0.53 to 1.29; p = 0.40), early mortality (OR:1.17; 95% CI: 0.63 to 2.17; p = 0.63), stroke, need for RVAD implantation, postoperative mitral valve regurgitation, major bleeding, or renal dysfunction. These findings suggest that concomitant MV surgery appears not to confer additional benefits in terms of these clinical outcomes. CONCLUSION: Based on the available evidence, concomitant MV surgery during LVAD implantation does not appear to have a significant impact on postoperative outcomes. However, decision-making regarding MV surgery should be individualized, considering patient-specific factors and characteristics. Further research with prospective studies focusing on specific patient populations and newer LVAD devices is warranted to provide more robust evidence and guide clinical practice in the management of valvular lesions in LVAD recipients.

Concomitant interventions in mitral valve surgery - A European perspective.

INTRODUCTION: In recent years, major findings on concomitant procedures and anticoagulation management have occurred in Mitral Valve (MV) surgery. Therefore, we sought to evaluate the current practices in MV interventions across Europe. METHODS: In October 2021, all national cardio-thoracic societies in the European region were identified following an electronic search and sent an online survey of 14 questions to distribute among their member consultant/attending cardiac surgeons. RESULTS: The survey was completed by 91 consultant/attending cardiac surgeons across 12 European countries, with 78% indicating MV repair as their specialty area. 57.1% performed >150 operations/year and 71.4% had 10+ years of experience.Concomitant tricuspid valve repair is performed for moderate tricuspid regurgitation (TR) by 69% of surgeons and for mild TR by 26.3%, both with annular diameter >40 mm. 50.6% indicated ischaemic MV surgery in patients undergoing CABG if moderate mitral regurgitation with ERO >20 mm2 and regurgitant volume >30 mL, and 45.1% perform it if severe MR with ERO >40 mm2 and regurgitant volume >60 mL. For these patients the preferred management was: MVR if predictors of repair failure identified (47.2%) and downsizing annuloplasty ring only (34.1%).For atrial fibrillation (AF) in cardiac surgery, 34.1% perform ablation with biatrial lesion and 20% with left sided only. 62.6% perform concomitant Left Atrial Appendage (LAA) Occlusion irrespective of AF ablation with a left atrial clip. A wide variability in anticoagulation strategies for MV repair and bioprosthetic MV valve was reported both for patients in sinus rhythm and AF. CONCLUSION: These results demonstrate a variable practice for MV surgery, and a degree of lack of compliance with surgical intervention guidelines and anticoagulation strategy.

Prognostic value of mitral regurgitation in patients undergoing left ventricular assist device deployment: A systematic review and meta-analysis.

BACKGROUND: Left ventricular assist devices (LVADs) represent an important therapeutic option for patients progressing to end-stage heart failure. LVAD has previously been shown to have a promising role in improving mitral regurgitation (MR). Nevertheless, the prognostic value of preoperative uncorrected MR in this population remains unclear. METHODS: A systematic database search with meta-analysis was conducted of comparative original articles of patients with preoperative mild MR (Grade 0-I) versus moderate-severe MR (Grade II-III) undergoing LVAD implantation, in EMBASE, MEDLINE, Cochrane database, and Google Scholar, from inception to June 2022. Primary outcomes were overall and operative mortality. Secondary outcomes were neurological dysfunction, gastrointestinal bleeding, right heart failure, LVAD thrombosis, and driveline infection. RESULTS: Our search yielded 2228 relevant studies. A total of 19 studies met the inclusion criteria with a total of 11 873 patients. LVAD caused a statistically significant decrease of 35.9% in the number of patients with moderate-severe MR (grade II-III) postoperatively. No significant difference was observed in terms of overall mortality, operative mortality, GI bleeding, LVAD thrombosis, and driveline infection rates between mild and moderate-severe MR. An increased rate of right heart failure was seen among patients with moderate-severe MR, while lower rates of neurological events were also observed. CONCLUSION: LVAD improves the haemodynamics of the left ventricle, to promote resolution of MR. Nevertheless, the severity of preoperative mitral regurgitation in patients undergoing LVAD deployment does not seem to affect mortality.

Re-emphasising the importance of histopathological diagnosis in suspected bacterial endocarditis.

Infective endocarditis (IE) carries a high risk of morbidity and mortality. Timely diagnosis, effective treatment and prompt recognition of complications are essential to favourable patient outcomes. A collaborative, multidisciplinary team approach to the management of IE has been shown to improve prognosis. However, the clinical heterogeneity of IE and atypical presentations pose challenges to the endocarditis team. We present a case highlighting the role of valve histopathology in suspected IE, where there may be diagnostic uncertainty.

Large animal model of vein grafts intimal hyperplasia: A systematic review.

Coronary artery bypass grafting remains the treatment of choice for a large cohort of patients with significant coronary disease. Despite the increased use of arterial grafts, the long saphenous vein remains the most commonly used conduit. Long-term graft patency continues to be the Achilles heel of saphenous vein grafts. This is due to the development of intimal hyperplasia, a chronic inflammatory disease that results in the narrowing and occlusion of a significant number of vein grafts. Research models for intimal hyperplasia are essential for a better understanding of pathophysiological processes of this condition. Large animal models resemble human anatomical structures and have been used as a surrogate to study disease development and prevention over the years. In this paper, we systematically review all published studies that utilized large animal models of vein graft disease with a focus on the type of model and any therapeutic intervention, specifically the use of external stents/mesh.

Instantaneous wave free ratio value impact on left internal mammary artery graft patency.

OBJECTIVES: To assess whether instantaneous wave - free ratio (iFR) value is associated with left internal mammary artery (LIMA) graft failure at 12 months follow-up post coronary artery bypass graft (CABG). BACKGROUND: Data suggests bypass to a non-significant left anterior descending artery (LAD) lesion due to visual over-estimation may lead to LIMA graft failure. Implementing iFR may result in better arterial graft patency. METHODS: In iCABG (iFR guided CABG) study patients planned to undergo an isolated CABG procedure was prospectively enrolled and iFR was performed for LAD. Coronary computed tomography angiography was performed at 2 and 12 months follow-up. The primary endpoint of this study was to determine the rate of LIMA graft occlusion or hypoperfusion at 2 and 12-months follow-up. We considered a composite secondary endpoint of Major adverse cardiovascular and cerebrovascular event (MACCE) as a secondary outcome. RESULTS: In total 69 patients were included with no differences regarding age, sex and risk factors. At 2 months, 50 of LIMAs with pre-CABG iFR median 0.855 (0.785 - 0.892) were patent. Hypoperfusion was found in 8 LIMAs (median iFR 0.88 (0.842 - 0.90)). While, 7 LIMAs (median iFR 0.91 (0.88 - 0.96)) were occluded (p = 0.04). At 12 months, when iFR of LAD was >0.85: just 12 (31.6% out of all patent LIMAS) grafts were patent and 24 (100.0% out of all hypoperfused/occluded) grafts were hypoperfused or occluded (p < 0.001). In terms of MACCE, no difference (p = 1.0) was found between all 3 groups divided according to iFR value. CONCLUSIONS: Instantaneous wave - free ratio value above 0.85 in LAD is a powerful tool predicting LIMA graft failure at 1-year follow up period.

Novel strategy for improved outcomes of extra-corporeal membrane oxygenation as a treatment for refractory post cardiotomy cardiogenic shock in the current era: a refreshing new perspective.

OBJECTIVES: Post-cardiotomy cardiogenic shock is an infrequent but important cause of death following cardiac surgery. Extra-corporeal membrane oxygenation offers the opportunity for temporary cardiovascular support and myocardial rest, with a view to recovery. We examine our results with our recently-implemented management algorithm. METHODS: We report our series of 15 consecutive patients out of 357 patients [4.2%] who required institution of veno-arterial extra-corporeal membrane oxygenation system support as treatment for Post-cardiotomy cardiogenic shock in the current era [January-2017 to January-2020]. RESULTS: The mean age was 64.3 ± 11.6 years (range: 40-82 years); there were 13 males (86.7%). Duration of veno-arterial extra-corporeal membrane oxygenation support was 6.7 ± 1.9 days. Duration of stay on intensive care unit [ICU] was 18.9 ± 17.1 days. Duration of hospital-stay was 28.3 ± 20.8 days. Survival to discharge and at 2.2 ± 0.9 years was 67%. CONCLUSIONS: We have shown clearly that veno-arterial extra-corporeal membrane oxygenation is an important rescue option for patients who develop refractory post-cardiotomy cardiogenic shock, with improved survival of 67% at 2.2 ± 0.9 years in those placed on post-cardiotomy veno-arterial extra corporeal membrane oxygenation support, which is superior to that reported hitherto in literature. We have sought to highlight the successes of post cardiotomy veno-arterial extra corporeal membrane oxygenation support, with improved results, based on careful patient selection, as well as diligent management of these critically-ill patients in the postoperative period, prior to establishment of irreversible end-organ dysfunction. Our strategy has also helped us rationalize and optimize the use of this expensive treatment modality.

Global longitudinal strain to determine optimal timing for surgery in primary mitral regurgitation: A systematic review.

BACKGROUND: Primary mitral regurgitation (PMR) results in adverse remodeling changes and left ventricular (LV) dysfunction. Assessing LV function has prognostic value in predicting morbidity and mortality. Indications for surgery include parameters such as LV ejection fraction (LVEF) and systolic dimensions. Current guidelines are limited in identifying patients at optimal time for surgery. Impaired postoperative LVEF indicates poor prognostic outcomes and subsequent heart failure. Global longitudinal strain (GLS) via speckle tracking echocardiography (STE) presents as a promising parameter to detect subclinical dysfunction in asymptomatic patients. METHODS: Following PRISMA guidelines, a literature search was conducted with Cochrane Library, PudMed, SCOPUS, and Web of Science. Key MeSH terms included "mitral regurgitation," "mitral valve insufficiency," "global longitudinal strain," "deformation," "LV-GLS," and "GLS." Inclusion criteria included (1) patients with severe PMR, (2) mixed population of symptomatic and asymptomatic patients, (3) standardized methods in assessing LV systolic function using 2D-STE, (4) valve repair or replacement surgery, and (5) patient outcomes measured after surgery. Search returned 234 papers, 12 of which met the inclusion criteria and were subsequently reviewed. RESULTS: Baseline GLS is an independent predictor of postoperative outcomes, ranging from -17.9 to -21.7% GLS. A significant negative correlation was observed between preoperative GLS and postoperative LVEF. Impaired baseline GLS was associated with higher mortality rates. Better long-term survival rates were seen in patients who underwent early surgery. CONCLUSION: GLS shows sensitivity in predicting long-term postoperative outcomes. Further analysis is required to determine preoperative GLS threshold to identify asymptomatic patients at the optimal time for mitral valve surgery.

Changes in right ventricular longitudinal function: primary mitral and concomitant tricuspid valve repair.

OBJECTIVES: To evaluate the impact of concomitant tricuspid valve (TV) repair on the right ventricular (RV) function postoperatively and within the 6 months following degenerative mitral valve (MV) repair. METHODS: The prospective study included 37 patients (mean age 57.32 ± 2.13 years) with severe MV regurgitation due to primary MV prolapse. Nineteen underwent successful MV repair (TV(-) group). Additional TV repair due to moderate-to-severe TV regurgitation was performed in 18 (TV(+) group). Two-dimensional (2D) speckle-tracking and tissue Doppler echocardiography was performed for all patients before surgery and 7 days and 6 months after surgery. RESULTS: Preoperative dimensions and indices of RV longitudinal function did not differ between the groups (right ventricle end-diastolic diameter (RVEDD) was 33.53 ± 0.94 mm vs. 34.67 ± 1.72 mm, tricuspid annular systolic motion (S') was 15.06 ± 0.85 cm/s vs. 16.0 ± 1.27 cm/s, tricuspid annular plane systolic excursion (TAPSE) was 24.02 ± 1.06 mm vs. 22.4 ± 1.36 mm, respectively; p>0.05). RVEDD decreased significantly and did not change within the follow-up in the TV(-) group. In the TV(+) group, RVEDD decreased early after surgery and more markedly six months later in comparison to the TV(-) group. Indices of RV systolic longitudinal function decreased early after surgery and had a tendency to increase after six months in both groups. Regional longitudinal strains of the lateral RV wall decreased early after surgery and improved within the six months in the TV(-) group and did not change significantly in the TV(+) group. CONCLUSIONS: Additional TV repair in degenerative MV repair more markedly reduces RV dimensions and does not have a negative impact on RV systolic function in comparison to an isolated MV repair although these conclusions are of limited value due to the lack of a control group.

Microdomain-Specific Modulation of L-Type Calcium Channels Leads to Triggered Ventricular Arrhythmia in Heart Failure.

RATIONALE: Disruption in subcellular targeting of Ca(2+) signaling complexes secondary to changes in cardiac myocyte structure may contribute to the pathophysiology of a variety of cardiac diseases, including heart failure (HF) and certain arrhythmias. OBJECTIVE: To explore microdomain-targeted remodeling of ventricular L-type Ca(2+) channels (LTCCs) in HF. METHODS AND RESULTS: Super-resolution scanning patch-clamp, confocal and fluorescence microscopy were used to explore the distribution of single LTCCs in different membrane microdomains of nonfailing and failing human and rat ventricular myocytes. Disruption of membrane structure in both species led to the redistribution of functional LTCCs from their canonical location in transversal tubules (T-tubules) to the non-native crest of the sarcolemma, where their open probability was dramatically increased (0.034±0.011 versus 0.154±0.027, P<0.001). High open probability was linked to enhance calcium-calmodulin kinase II-mediated phosphorylation in non-native microdomains and resulted in an elevated ICa,L window current, which contributed to the development of early afterdepolarizations. A novel model of LTCC function in HF was developed; after its validation with experimental data, the model was used to ascertain how HF-induced T-tubule loss led to altered LTCC function and early afterdepolarizations. The HF myocyte model was then implemented in a 3-dimensional left ventricle model, demonstrating that such early afterdepolarizations can propagate and initiate reentrant arrhythmias. CONCLUSIONS: Microdomain-targeted remodeling of LTCC properties is an important event in pathways that may contribute to ventricular arrhythmogenesis in the settings of HF-associated remodeling. This extends beyond the classical concept of electric remodeling in HF and adds a new dimension to cardiovascular disease.

An unusual presentation of ischaemic mitral regurgitation as P2 prolapse.

A 54-year-old gentleman presented with pulmonary oedema secondary to anterolateral papillary muscle (PPM) rupture and acute mitral regurgitation subsequent to myocardial ischaemia (MI). Angiography revealed complete occlusion of the first obtuse marginal (OM1) branch of the circumflex coronary artery and a 70% occlusion of the left anterior descending (LAD) coronary artery. Operatively, unusual anatomy was noted; an accessory head was attached superiorly to the anterior lateral PPM. This gave rise to chordae that were subsequently attached to the posterior second (P2) scallop. Additionally, the P2 scallop was deficient in chordae from the posteromedial PPM, thus, loss of this accessory head led to severe mitral regurgitation. We review the PPM anatomy and pathological context of PPM rupture and ischaemic mitral regurgitation.

Continuous bilateral thoracic paravertebral blockade for analgesia after cardiac surgery: a randomised, controlled trial.

BACKGROUND: Continuous bilateral thoracic paravertebral blockade has been used for analgesia after cardiac surgery, but its efficacy has never been formally tested. METHOD: Fifty adult patients were enrolled in a double-blind, randomised, controlled study of continuous bilateral thoracic paravertebral infusion of 0.5% lidocaine (1 mg.kg-1.hr-1) for analgesia after coronary surgery. Control patients received a subcutaneous infusion of lidocaine at the same rate through catheters inserted at the same locations as the study group. The primary outcome was morphine consumption at 48 hours using patient-controlled analgesia (PCA). Secondary outcomes included pain, respiratory function, nausea and vomiting. Serum lidocaine concentrations were measured on the first two post-operative days. RESULTS: There was no difference in morphine consumption or in any other outcome measure between the groups. Serum lidocaine concentrations increased during the study, with a maximum of 5.9 mg.l-1. There were no adverse events as a consequence of the study. CONCLUSION: Bilateral paravertebral infusion of lidocaine confers no advantage over systemic lidocaine infusion after cardiac surgery. CLINICAL TRIAL REGISTRATION: ISRCTN13424423 ( https://www.isrctn.com ).

Are adjunct subvalvular techniques more effective than isolated restrictive annuloplasty for treating ischemic mitral regurgitation?

This review focused on whether subvalvular techniques are more effective than isolated restrictive annuloplasty in addressing ischemic mitral regurgitation (MR). Searching identified 445 papers and, following a selection process, we ended up with 10 articles. Two were propensity-matched studies, four retrospective and four prospective, non-randomized studies. The end points of interest were late recurrence of MR, other early echocardiographic outcomes of mitral function and early mortality. All studies focusing on echocardiographic measurements showed improved results in the groups where subvalvular repair techniques were used. In almost all studies, the recurrence of MR postoperatively was less when subvalvular techniques were used. No difference in early or in-hospital mortality was demonstrated in all four studies that included comparisons. We conclude that subvalvular techniques in combination with annuloplasty are safe and may better address ischemic MR than the use of annuloplasty ring alone.

The value of adding sub-valvular procedures for chronic ischemic mitral regurgitation surgery: a meta-analysis.

BACKGROUND: The most performed repair technique for the treatment of chronic ischemic mitral regurgitation in patients referred for bypass grafting remains restricted annuloplasty. However, it is associated with a high rate of failure, especially if severe tenting exists. OBJECTIVES: To understand if adjunctive sub-valvular mitral procedures may provide better repair performance. METHODS: A systematic literature review identified six studies of which five fulfilled the criteria for meta-analysis. Outcomes for a total of 404 patients (214 had adjunctive sub-valvular procedures and 190 restricted annuloplasty) were meta-analyzed using random effects modeling. Heterogeneity and subgroup sensitivity analysis were assessed. Primary endpoints were: late recurrence of moderate mitral regurgitation, left ventricle remodeling and coaptation depth at follow-up. Secondary endpoints were: early mortality, mid-term survival and operative outcomes. RESULTS: Sub-valvular procedure technique was associated with a significantly lower late recurrence of mitral regurgitation (Odds ratio (OR) 0.34, 95% Confidence Interval (CI) [0.18, 0.65], p=0.0009), smaller left ventricle end-systolic diameter (Weighted Mean Difference (WMD) -4.06, 95% CI [-6.10, -2.03], p=0.0001) and reduced coaptation depth (WMD -2.36, 95% CI [-5.01, -0.71], p=0.009). These findings were consistent, even in studies that included patients at high risk for repair failure (coaptation depth >10 mm and tenting area >2.5 cm2). A low degree of heterogeneity was observed. There was no difference in terms of early mortality and mid-term survival; sub-valvular technique was associated with prolonged cardiopulmonary and cross-clamp time. CONCLUSIONS: Adding sub-valvular procedures when repairing ischemic chronic mitral valve regurgitation may be associated with better durability, even in the case of the presence of predictors for late failure. PERSPECTIVE: Surgical sub-valvular adjunctive procedures have to be considered in the case of the presence of echocardiographic predictors for late failure.

Direct Evidence for Microdomain-Specific Localization and Remodeling of Functional L-Type Calcium Channels in Rat and Human Atrial Myocytes.

BACKGROUND: Distinct subpopulations of L-type calcium channels (LTCCs) with different functional properties exist in cardiomyocytes. Disruption of cellular structure may affect LTCC in a microdomain-specific manner and contribute to the pathophysiology of cardiac diseases, especially in cells lacking organized transverse tubules (T-tubules) such as atrial myocytes (AMs). METHODS AND RESULTS: Isolated rat and human AMs were characterized by scanning ion conductance, confocal, and electron microscopy. Half of AMs possessed T-tubules and structured topography, proportional to cell width. A bigger proportion of myocytes in the left atrium had organized T-tubules and topography than in the right atrium. Super-resolution scanning patch clamp showed that LTCCs distribute equally in T-tubules and crest areas of the sarcolemma, whereas, in ventricular myocytes, LTCCs primarily cluster in T-tubules. Rat, but not human, T-tubule LTCCs had open probability similar to crest LTCCs, but exhibited ≈ 40% greater current. Optical mapping of Ca(2+) transients revealed that rat AMs presented ≈ 3-fold as many spontaneous Ca(2+) release events as ventricular myocytes. Occurrence of crest LTCCs and spontaneous Ca(2+) transients were eliminated by either a caveolae-targeted LTCC antagonist or disrupting caveolae with methyl-ß-cyclodextrin, with an associated ≈ 30% whole-cell ICa,L reduction. Heart failure (16 weeks post-myocardial infarction) in rats resulted in a T-tubule degradation (by ≈ 40%) and significant elevation of spontaneous Ca(2+) release events. Although heart failure did not affect LTCC occurrence, it led to ≈ 25% decrease in T-tubule LTCC amplitude. CONCLUSIONS: We provide the first direct evidence for the existence of 2 distinct subpopulations of functional LTCCs in rat and human AMs, with their biophysical properties modulated in heart failure in a microdomain-specific manner.

Early Results of Rheumatic Mitral Valve Repair.

BACKGROUND AND AIM OF THE STUDY: Mitral valve repair (MVr) in rheumatic heart disease (RHD) remains challenging. The present authors' surgical experience of MVr in 56 patients with RHD operated in between January 2011 and September 2014 is reported. METHODS: Among the patients (mean age 32 ± 11 years), 11 were in NYHA functional class II, 32 in class III, and seven in class IV. An adequate or oversized autologous pericardial patch was sutured to extend the coaptating edge of both the anterior leaflet (in 18 patients) and the posterior leaflet (in 30 patients). Neochordae were implanted as needed (n = 43), and leaflet thinning (n = 13), commissurotomy (n = 15) and chordal splitting (n = 9) were also performed. A rigid annuloplasty ring was implanted in 32 patients, and in 24 patients a complete flexible annuloplasty ring made from pericardium, 4 mm Gore-Tex tube graft or a Dacron patch was constructed. Repair was not attempted in 16 patients, with replacement using a mechanical bileaflet prosthesis being considered the only option. RESULTS: Intraoperative post-repair transesophageal echocardiography demonstrated competency, with trivial mitral regurgitation (MR) up to grade I in all patients and a minimum coaptation depth ≥5 mm. There were no intraoperative or in-hospital deaths. Clinical and echocardiographic evaluations were performed up to six weeks after surgery, at which time 51 patients were in NYHA classes I-II and five were in class III. Residual mild MR up to grade I was identified in six patients. No recurrence of MR was observed in any of the patients, and no patients were reoperated on. CONCLUSIONS: The lack of adequate access to anticoagulation medication and monitoring, in addition to religious/cultural bias to the type of prosthetic valve used in low-income countries, necessitates an increase in the numbers of rheumatic MVr.