Hybrid Transcatheter Approach to an Iatrogenic Left Ventricle-Coronary Sinus Fistula

This clinical case describes a subacute presentation of decompensated heart failure secondary to an iatrogenic left ventricle-to-coronary sinus fistula after sequential mitral valve surgical procedures. Computed tomography was used to select an unconventional hybrid transapical access approach and facilitate successful closure using a vascular plug.

Association of Volume and Outcomes in 234,556 Patients Undergoing Surgical Aortic Valve Replacement

BACKGROUND

The relationship between institutional volume and operative mortality following SAVR remains unclear.

METHODS

From 1/2013 to 6/2018, 234,556 patients underwent isolated SAVR (n=144,177) or SAVR+CABG (n=90,379) within the STS ACSD. The association between annualized SAVR volume [Group 1 (1-25 SAVR), Group 2 (26-50 SAVR), Group 3 (51-100 SAVR), and Group 4 (>100 SAVR)] and operative mortality and composite major morbidity/mortality was assessed. Random effects models were used to evaluate whether historic (2013-2015) SAVR volume or risk-adjusted outcomes explained future (2016-2018) risk-adjusted outcomes.

RESULTS

The annualized median number of SAVRs per site was 35 [IQR: 22-59, isolated AVR: 20, AVR+CABG: 13]. Among isolated SAVR cases, the mean operative mortality and composite morbidity/mortality were 1.5% and 9.7%, respectively, at the highest volume sites (Group 4); with significantly higher rates among progressively lower volume groups (p-trend<0.001). After adjustment, lower volume centers experienced increased odds of operative mortality [Group 1 vs. 4 (Ref): AOR (SAVR), 2.24 (1.91-2.64); AOR (SAVR+CABG), 1.96 (1.67-2.30)] and major morbidity/mortality [AOR (SAVR), 1.53 (1.39-1.69); AOR (SAVR+CABG), 1.46 (1.32-1.61)] compared to the highest volume institutions. Substantial variation in outcomes was observed across hospitals within each volume category and prior outcomes explained a greater proportion of hospital operative outcomes than prior volume.

CONCLUSIONS

Operative outcomes following SAVR±CABG is inversely associated with institutional procedure volumes; however, prior outcomes are more predictive than prior volume of future outcomes. Given excellent outcomes observed at many lower volume hospitals, procedural outcomes may be preferable to procedural volumes as a quality metric.

The International Society for Minimally Invasive Cardiothoracic Surgery Expert Consensus Statement on Transcatheter and Surgical Aortic Valve Replacement in Low- and Intermediate-Risk Patients: A Meta-Analysis of Randomized and Propensity-Matched Studies

OBJECTIVE

There is an increasing amount of evidence supporting use of transcatheter aortic valve replacement (TAVR) for treatment of aortic stenosis in patients at low or intermediate risk for surgical aortic valve replacement (SAVR). TAVR is now approved for use in all patient cohorts. Despite this, there remains debate about the relative efficacy of TAVR compared with SAVR in lower-risk cohorts and various subgroups of patients. We performed a systematic review and meta-analysis of randomized controlled trials (RCTs) and propensity-matched trials to guide a consensus among expert cardiologists and surgeons.

METHODS

Studies comparing TAVR and SAVR in low- and intermediate-risk patients were identified by a thorough search of the major databases. Mortality, stroke, and other perioperative outcomes were assessed at 30 days and 1 year.

RESULTS

Early mortality was lower in TAVR compared to SAVR in RCTs, but not propensity-matched studies in low-risk cohorts (0.66% vs 1.5%; odds ratio [OR] = 0.44, 95% confidence interval [CI] 0.20 to 0.98, I² = 0%). No difference in mortality between TAVR and SAVR was identified in intermediate-risk patients at early or later time points. Incidence of perioperative stroke in 3 low-risk RCTs was significantly lower in TAVR (0.4%) than SAVR (1.4%; OR = 0.33, 95% CI 0.13 to 0.81, I² = 0%). There was no difference in stroke for intermediate-risk patients between TAVR and SAVR. The expert panel of cardiologists and cardiac surgeons provided recommendations for TAVR and SAVR in various clinical scenarios.

CONCLUSIONS

In RCTs comparing TAVR and SAVR in low-risk patients, early mortality and stroke were lower in TAVR, but did not differ at 1 year. There was no difference in mortality and stroke in intermediate-risk patients. The Multidisciplinary Heart Team must consider individual patient characteristics and preferences when recommending TAVR or SAVR. The decision must consider the long-term management of each patient's aortic valve disease.

Contemporary Surgical and Transcatheter Management of Mitral Annular Calcification

BACKGROUND

The presence of mitral annular calcification (MAC) in patients with mitral valve (MV) stenosis or regurgitation is a difficult scenario for surgeons and the heart team. Patients with MAC most often have a significant number of comorbidities that exclude them as surgical candidates. This review highlights the various contemporary techniques available to manage MAC during treatment of the MV.

METHODS

This study is a focused review of the anatomy, pathology, and management of MAC. The review describes the surgical and transcatheter techniques with outcomes, where available.

RESULTS

The incidence of MAC is between 5% and 42% in patients with severe MV disease. The pathophysiology underlying MAC is not yet clear, but it most likely is related to processes of inflammation and atherosclerosis. Surgical techniques can be grouped into those in which the MAC is completely resected en bloc and those in which the MAC is incompletely resected or left in situ. Transcatheter therapies are feasible in some patients, but they have been limited by the anatomic constraints of MAC; most importantly left ventricular outflow tract obstruction and paravalvular regurgitation.

CONCLUSIONS

Surgeons as part of the heart team now have a range of techniques to manage MAC in those patients with severe MV disease. Transcatheter therapies may increase the options for patients whose surgical risk is too high.

Valve-Sparing Root Replacement Versus Composite Valve Grafting in Aortic Root Dilation: A Meta-Analysis

BACKGROUND

Aortic valve-sparing operations theoretically have fewer stroke and bleeding complications but may increase late reoperation risk versus composite valve grafts.

METHODS

We meta-analyzed all studies comparing aortic valve-sparing (reimplantation and remodelling) and composite valve-grafting (bioprosthetic and mechanical) procedures. Early outcomes were all-cause mortality, reoperation for bleeding, myocardial infarction, and thromboembolism/stroke. Long-term outcomes included all-cause mortality, reintervention, bleeding, and thromboembolism/stroke. Studies exclusively investigating dissection or pediatric populations were excluded.

RESULTS

A total of 3794 patients who underwent composite valve grafting and 2424 who underwent aortic valve-sparing procedures were included from 9 adjusted and 17 unadjusted observational studies. Mean follow-up was 5.8 ± 3.0 years. Aortic valve sparing was not associated with any difference in early mortality, bleeding, myocardial infarction, or thromboembolic complications. Late mortality was significantly lower after valve sparing (incident risk ratio, 0.68; 95% confidence interval [CI], 0.54-0.87; P < .01). Late thromboembolism/stroke (incident rate ratio, 0.36; 95% CI, 0.22-0.60; P < .01) and bleeding (incident rate ratio, 0.21; 95% CI, 0.11-0.42; P < .01) risks were lower after valve sparing. Procedure type did not affect late reintervention.

CONCLUSIONS

Aortic valve sparing appears to be safe and associated with reduced late mortality, thromboembolism/stroke, and bleeding compared with composite valve grafting. Late durability is equivalent. Aortic valve sparing should be considered in patients with favorable aortic valve morphology.

Smoking and TAVR

See Article Qintar et al.

Valve-in-Valve TAVR: State-of-the-Art Review

An increasing number of surgically implanted bioprostheses will require re-intervention for structural valve deterioration. Valve-in-valve transcatheter aortic valve replacement (ViV TAVR) has become an alternative to reoperative surgery, currently approved for high-risk and inoperable patients. Challenges to the technique include higher rates of prosthesis–patient mismatch and coronary obstruction, compared to native valve TAVR. Herein, we review results of ViV TAVR and novel techniques to overcome the aforementioned challenges.

Coronary Artery Bypass Grafting With and Without Manipulation of the Ascending Aorta: A Network Meta-Analysis

BACKGROUND

Coronary artery bypass grafting (CABG) remains the standard of treatment for 3-vessel and left main coronary disease, but is associated with an increased risk of post-operative stroke compared to percutaneous coronary intervention. It has been suggested that CABG techniques that eliminate cardiopulmonary bypass and reduce aortic manipulation may reduce the incidence of post-operative stroke.

OBJECTIVES

A network meta-analysis was performed to compare post-operative outcomes between all CABG techniques, including anaortic off-pump CABG (anOPCABG), off-pump with the clampless Heartstring device (OPCABG-HS), off-pump with a partial clamp (OPCABG-PC), and traditional on-pump CABG with aortic cross-clamping.

METHODS

A systematic search of 6 electronic databases was performed to identify all publications reporting the outcomes of the included operations. Studies reporting the primary endpoint, 30-day post-operative stroke rate, were included in a Bayesian network meta-analysis.

RESULTS

There were 13 included studies with 37,720 patients. At baseline, anOPCABG patients had higher previous stroke than did the OPCABG-PC (7.4% vs. 6.5%; p = 0.02) and CABG (7.4% vs. 3.2%; p = 0.001) patients. AnOPCABG was the most effective treatment for decreasing the risk of post-operative stroke (-78% vs. CABG, 95% confidence interval [CI]: 0.14 to 0.33; -66% vs. OPCABG-PC, 95% CI: 0.22 to 0.52; -52% vs. OPCABG-HS, 95% CI: 0.27 to 0.86), mortality (-50% vs. CABG, 95% CI: 0.35 to 0.70; -40% vs. OPCABG-HS, 95% CI: 0.38 to 0.94), renal failure (-53% vs. CABG, 95% CI: 0.31 to 0.68), bleeding complications (-48% vs. OPCABG-HS, 95% CI: 0.31 to 0.87; -36% vs. CABG, 95% CI: 0.42 to 0.95), atrial fibrillation (-34% vs. OPCABG-HS, 95% CI: 0.49 to 0.89; -29% vs. CABG, 95% CI: 0.55 to 0.87; -20% vs. OPCABG-PC, 95% CI: 0.68 to 0.97), and shortening the length of intensive care unit stay (-13.3 h; 95% CI: -19.32 to -7.26; p < 0.0001).

CONCLUSIONS

Avoidance of aortic manipulation in anOPCABG may decrease the risk of post-operative stroke, especially in patients with higher stroke risk. In addition, the elimination of cardiopulmonary bypass may reduce the risk of short-term mortality, renal failure, atrial fibrillation, bleeding, and length of intensive care unit stay.

KCa1.1, a calcium-activated potassium channel subunit alpha 1, is targeted by miR-17-5p and modulates cell migration in malignant pleural mesothelioma

Background

Malignant pleural mesothelioma (MPM) is an aggressive, locally invasive, cancer elicited by asbestos exposure and almost invariably a fatal diagnosis. To date, we are one of the leading laboratory that compared microRNA expression profiles in MPM and normal mesothelium samples in order to identify dysregulated microRNAs with functional roles in mesothelioma. We interrogated a significant collection of MPM tumors and normal pleural samples in our biobank in search for novel therapeutic targets.

Methods

Utilizing mRNA-microRNA correlations based on differential gene expression using Gene Set Enrichment Analysis (GSEA), we systematically combined publicly available gene expression datasets with our own MPM data in order to identify candidate targets for MPM therapy.

Results

We identified enrichment of target binding sites for the miR-17 and miR-30 families in both MPM tumors and cell lines. RT-qPCR revealed that members of both families were significantly downregulated in MPM tumors and cell lines. Interestingly, lower expression of miR-17-5p (P = 0.022) and miR-20a-5p (P = 0.026) was clearly associated with epithelioid histology. We interrogated the predicted targets of these differentially expressed microRNA families in MPM cell lines, and identified KCa1.1, a calcium-activated potassium channel subunit alpha 1 encoded by the KCNMA1 gene, as a target of miR-17-5p. KCa1.1 was overexpressed in MPM cells compared to the (normal) mesothelial line MeT-5A, and was also upregulated in patient tumor samples compared to normal mesothelium. Transfection of MPM cells with a miR-17-5p mimic or KCNMA1-specific siRNAs reduced mRNA expression of KCa1.1 and inhibited MPM cell migration. Similarly, treatment with paxilline, a small molecule inhibitor of KCa1.1, resulted in suppression of MPM cell migration.

Conclusion

These functional data implicating KCa1.1 in MPM cell migration support our integrative approach using MPM gene expression datasets to identify novel and potentially druggable targets.

Electronic supplementary material

The online version of this article (doi:10.1186/s12943-016-0529-z) contains supplementary material, which is available to authorized users.

Surgical Pulmonary Embolectomy: Experience in a Series of 37 Consecutive Cases

BACKGROUND

Massive pulmonary embolism is a poorly tolerated condition. Treatment options in this condition include anticoagulation and primary reperfusion therapy - systemic thrombolysis, catheter based treatments or surgical embolectomy. There is little data on the relative efficacy of each treatment.

METHODS

The preoperative characteristics and outcomes of patients referred for surgical embolectomy between 2000-2014 was reviewed. Echocardiography was performed in the majority of patients before and after surgery.

RESULTS

Thirty-seven patients underwent pulmonary embolectomy between 2000-2014. One patient died within 30 days, another before leaving hospital. All other patients were alive at the time of follow-up (survival 94.6% at median 36 months). Median ventilation time was 24hours. Median hospital length of stay was 10.5 days. There was echocardiographic evidence of severe right ventricular strain (increased size and decreased function) before surgery, which was significantly improved to within the normal range by discharge, and follow-up.

CONCLUSIONS

Surgical embolectomy is a safe procedure, with low mortality, improved postoperative right ventricular function and pulmonary pressure, and good long-term outcome. Early relief of a large proportion of the clot burden can be life-saving. There should be consideration for its use as an initial treatment strategy in patients with massive or submassive pulmonary embolus with a large burden of proximal clot. A multidisciplinary approach for the treatment of these patients is required.