Does Sustained Reduction of Functional Mitral Regurgitation Impact Survival?

Functional mitral regurgitation (FMR) is associated with increased mortality and has been considered a marker for advanced heart disease, yet the value of mitral valve repair (MVr) in this population remains unclear. This study aims to evaluate the impact of reducing FMR burden through surgical MVr on survival. Patients with severe FMR who underwent MVr with an undersized, complete, rigid, annuloplasty between 2004 and 2017 were assessed (n = 201). Patients were categorized based on grade of recurrent FMR (0-4). Time-to-event Kaplan-Meier estimations of freedom from death or reoperation were performed using the log-rank test. Cox proportional hazards models evaluated all-cause mortality and reported in hazards ratios (HR) and 95% confidence intervals (CI). Patients were categorized by postoperative recurrent FMR: 45% (91/201) of patients had grade 0, 29% (58/201) grade 1, 20% (40/201) grade 2, 2% (4/201) grade 3%, and 4% (8/201) grade 4. The cumulative incidence of reoperation with death as a competing risk was higher in patients with grades ≥3 recurrent FMR compared to grades ≤2 (44.6% vs 14.6%, subhazard ratio 3.69 [95% CI, 1.17-11.6]; P = 0.026). Overall freedom from death or reoperation was superior for recurrent FMR grades ≤2 compared to grades ≥3 (log-rank P < 0.001). Increasing recurrent FMR grade was independently associated with mortality (HR 1.30 [95% CI, 1.07-1.59] P = 0.009). Reduced postoperative FMR grade resulted in an incrementally lower risk of death or reoperation after MVr. These results suggest that achieving a durable reduction in FMR burden improves long-term survival.

Ultrasonic Emulsification of Severe Mitral Annular Calcification During Mitral Valve Replacement.

PURPOSE: Severe mitral annular calcification (MAC) increases surgical complexity and is independently associated with increased operative mortality for mitral valve replacement (MVR). Recently we adopted ultrasonic emulsification/aspiration for annular decalcification to address these risks and describe our early experience with this new technology. DESCRIPTION: Excluding previous mitral valve surgery or endocarditis, 179 patients with MAC underwent MVR at a single institution between January 2015 and March 2020. Of these, 15 consecutive patients with severe MAC (≥50% of the annulus) underwent annular decalcification with ultrasonic emulsification/aspiration as an adjunct treatment during MVR from April 2019 to March 2020. EVALUATION: Mean patient age was 68 ± 12 years, and 72% (n = 128) were female. Mean preoperative left ventricular ejection fraction was 60% ± 11%, and mean mitral valve gradient was 9.1 ± 4.4 mm Hg. Concomitant procedures included antiarrhythmia (n = 52), aortic valve replacement (n = 32), and coronary artery bypass grafting (n = 20). There were no operative deaths or strokes in the group undergoing ultrasonic emulsification and aspiration. CONCLUSIONS: The use of ultrasonic emulsification and aspiration in severe MAC patients may help mitigate the risks of MVR and facilitate operative success in this challenging, high-risk population.

Rheumatic mitral valve repair or replacement in the valve-in-valve era.

OBJECTIVE: For degenerative mitral disease, repair is superior to replacement; however, the best operative strategy for rheumatic mitral disease remains unclear. We evaluated the association between decision-making in choosing repair versus replacement and outcomes across 2 decades of rheumatic mitral surgery. METHODS: Patients undergoing isolated, first-time rheumatic mitral surgery were identified. Era 1 (1997-2008) and Era 2 (2009-2018) were distinguished by intraoperative assessment of anterior leaflet mobility/calcification (Era 2) in deciding between mitral repair versus replacement. Primary outcome was a composite of death, reoperation, and severe valve dysfunction. RESULTS: Among 180 patients, age was 59 ± 14 years, and ejection fraction was 58% ± 10%. A higher proportion in Era 1 (n = 56) compared with Era 2 (n = 124) had preoperative atrial fibrillation (68% vs 46%; P = .006); the groups were otherwise similar. Primary indication was mitral stenosis in 69% (124 out of 180; pure = 35, mixed = 89) and did not differ by era (P = .67). During Era 1, 70% (39 out of 56) underwent repair, compared with 33% (41 out of 124) during Era 2 (P < .001). Freedom from death, reoperation, or severe valve dysfunction at 5 years was higher in Era 2 (72% ± 9%) than Era 1 (54% ± 13%; P = .04). Five-year survival was higher in Era 2 than Era 1, but did not differ between repair versus replacement. Five-year cumulative incidence of reoperation with death as a competing risk did not differ by era, but was higher after repair than replacement. CONCLUSIONS: Careful assessment of anterior leaflet mobility/calcification to determine mitral repair or replacement was associated with improved outcomes. This decision-making strategy may alter the threshold for rheumatic mitral replacement in the current valve-in-valve era.

High SARS-CoV-2 Viral Load in Urine Sediment Correlates with Acute Kidney Injury and Poor COVID-19 Outcome.

BACKGROUND: AKI is a complication of coronavirus disease 2019 (COVID-19) that is associated with high mortality. Despite documented kidney tropism of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), there are no consistent reports of viral detection in urine or correlation with AKI or COVID-19 severity. Here, we hypothesize that quantification of the viral load of SARS-CoV-2 in urine sediment from patients with COVID-19 correlates with occurrence of AKI and mortality. METHODS: The viral load of SARS-CoV-2 in urine sediments (U-viral load) was quantified by qRT-PCR in 52 patients with PCR-confirmed COVID-19 diagnosis, who were hospitalized between March 15 and June 8, 2020. Immunolabeling of SARS-CoV-2 proteins Spike and Nucleocapsid was performed in two COVID-19 kidney biopsy specimens and urine sediments. Viral infectivity assays were performed from 32 urine sediments. RESULTS: A total of 20 patients with COVID-19 (39%) had detectable SARS-CoV-2 U-viral load, of which 17 (85%) developed AKI with an average U-viral load four-times higher than patients with COVID-19 who did not have AKI. U-viral load was highest (7.7-fold) within 2 weeks after AKI diagnosis. A higher U-viral load correlated with mortality but not with albuminuria or AKI stage. SARS-CoV-2 proteins partially colocalized with the viral receptor ACE2 in kidney biopsy specimens in tubules and parietal cells, and in urine sediment cells. Infective SARS-CoV-2 was not detected in urine sediments. CONCLUSION: Our results further support SARS-CoV-2 kidney tropism. A higher SARS-CoV-2 viral load in urine sediments from patients with COVID-19 correlated with increased incidence of AKI and mortality. Urinary viral detection could inform the medical care of patients with COVID-19 and kidney injury to improve prognosis.

Anterior versus posterior leaflet mitral valve repair: A propensity-matched analysis.

OBJECTIVE: Mitral valve repair is superior to replacement for degenerative disease, but long-term outcomes of anterior versus posterior leaflet repair remain poorly defined. We propensity matched anterior and posterior repairs to compare long-term outcomes. METHODS: Patients undergoing first-time degenerative mitral repair between 1992 and 2018 were identified. Primary outcome was overall survival. Secondary outcomes were postprocedural residual mitral regurgitation and reoperation. From 1025 patients, 1:1 propensity score matching was performed, yielding 309 anterior (isolated anterior = 85, bileaflet = 224) and 309 isolated posterior repairs. RESULTS: Age was 58 ± 15 years, ejection fraction was 57% ± 10%, and matched groups were well balanced. Anterior repairs had longer bypass (122 ± 53 vs 109 ± 43 minutes, P = .001) and crossclamp (94 ± 44 vs 85 ± 62 minutes, P = .033) times. Mean residual mitral regurgitation grade was 0.44 (95% confidence interval, 0.24-0.65) for anterior repair and 0.30 (95% confidence interval, 0.13-0.47) for posterior repair (P = .31). Overall, 92% (569/618) of matched patients had no residual mitral regurgitation, with no differences in mitral regurgitation grade between groups (P = .77). Survival did not differ between anterior (10 years: 72% ± 7%; 15 years: 63% ± 7%) and posterior (10 years: 74% ± 7%; 15 years: 60% ± 8%) groups (log-rank P = .93). Linearized incidence of reoperation was 0.62% per patient-year, including 0.74% for anterior and 0.48% for posterior repairs. Cumulative incidence of reoperation at 15 years was 7.5% after anterior repair and 4.9% after posterior repair (Gray's test P = .26). CONCLUSIONS: No long-term survival or reoperation difference was found between posterior and anterior repair. On the basis of these findings, surgeons at centers of excellence should aim for repair of both anterior and posterior leaflet pathology with the same decision-making threshold over valve replacement for degenerative mitral disease.

Inflammatory and Antioxidant Gene Transcripts: A Novel Profile in Postoperative Atrial Fibrillation.

Postoperative atrial fibrillation (POAF) is the most common complication after cardiac surgery; however, antiarrhythmic strategies have not lowered the rate of POAF. This study aimed to identify specific gene transcripts of atrial inflammation, inflammatory handling, and oxidative stress associated with POAF. Left atrial tissue was obtained from 50 patients undergoing intended degenerative mitral repair who did not have any of the following risk factors for POAF: history of atrial fibrillation or other arrhythmia, left atrial diameter greater than 6.0 cm, or left ventricular ejection fraction less than 40%. Postoperative outcomes and left atrial tissue messenger ribonucleuc acid (mRNA) levels were recorded. Parametric 2-sample t-tests and chi-square tests were used to evaluate for statistical significance in comparing POAF and non-POAF groups. Within 30 days of surgery, 19 of 50 of patients (38%) developed POAF. There were no significant preoperative, intraoperative, or postoperative differences between POAF and non-POAF patients. In the tissue transcriptome analysis, POAF patients were found to have a worse preoperative inflammatory state with higher levels of tumor necrosis factor alpha, Interleukin-6, and nuclear factor of kappa light polypeptide gene enhancer in B-cells mRNA, worse inflammatory handling capacity with lower levels of nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor mRNA, and reduced antioxidant defenses with lower levels of glutathione synthetase, glutathione reductase, and mitochondrial superoxide dismutase 2 mRNA. This study found POAF patients to have preoperative left atrial tissue profiles suggestive of more inflammation, worse inflammatory handling, and reduced antioxidant defenses against oxidative stress. Investigation of therapies targeted to the tissue-specific inflammatory transcriptome of POAF patients is warranted.

Anticoagulation following mitral valve repair.

BACKGROUND AND AIM: Anticoagulation after mitral valve repair is controversial and guidelines are not well-established. This study evaluated the association between postoperative warfarin use and complications after mitral valve repair, including bleeding and thromboembolic incidents, readmission, and mortality. METHODS: This retrospective study investigated 1097 patients who underwent elective mitral valve repair between April 2003 and March 2017, and was naïve to atrial fibrillation or prior cardiac surgery. This cohort had no other indication for or against anticoagulation. About 775 patients were placed on warfarin with international normalized ratio goal 2.5 and 322 patients were not anticoagulated. The association between anticoagulation and complications was assessed with univariate comparisons between groups and multiple logistic regression. RESULTS: Postoperative warfarin use was associated with a reduced composite of bleeding and thromboembolic complications (pulmonary embolism, TIA, stroke, pericardial effusion or cardiac tamponade, gastrointestinal bleeding, and reoperation for bleeding) with an odds ratio of 0.29 (95% confidence interval, 0.13-0.64, P = .003). There was no difference in 30-day or 6-month mortality or readmission rate between groups. Long-term survival estimates were superior in the warfarin group (10-year: 92% vs 85%; log-rank P < .001). CONCLUSIONS: Our analysis showed that postoperative warfarin use was associated with an overall reduced composite of bleeding and thromboembolic incidents and superior long-term survival. These findings suggest that anticoagulation with warfarin following mitral valve repair may be a safe and effective means for avoiding postoperative complications and that a large prospective randomized clinical trial is warranted.

Degenerative Mitral Valve Repair Restores Life Expectancy.

BACKGROUND: Mitral valve repair (MVr) for severe, degenerative mitral regurgitation is the gold standard, because medical management carries poor prognosis. However, despite clear benefit of MVr, many eligible patients are untreated. This study investigated whether MVr restores patients to normal life expectancy, at any age of operation, by comparing long-term survival of patients after MVr with the life expectancy of the general United States population. METHODS: This retrospective study investigated 1011 patients with degenerative mitral regurgitation who underwent isolated MVr between 2003 and 2017. Parametric distribution analysis was applied to long-term post-MVr mortality data, and Weibull probability plots provided the best-fit distribution by Anderson-Darling Goodness-of-Fit testing. Confidence intervals of the estimated distribution were used to compare additional life expectancy after MVr to the general US population across multiple decades of life. Patients after MVr were categorized by age into decade (range, 20-89 years). RESULTS: The life expectancy of patients after MVr matched the life expectancy of the general US population at any age between 40 and 89 years. Lower-bound one-sided 95% confidence intervals for additional life expectancy were not appreciably different from corresponding median additional life expectancy of the general population. There were few deaths in the 20- to 39-year-old group, limiting predictability, but survival also appeared normative. CONCLUSIONS: These findings suggest that degenerative MVr restores anticipated life expectancy to that of the general population, regardless of age. Although our findings underscore the importance of repair for degenerative mitral disease, larger studies with longer term follow-up are needed to reinforce this finding, particularly for younger patients.