Cardiology

Muller, D. W., R. S. Farivar, P. Jansz, R. Bae, D. Walters, A. Clarke, P. A. Grayburn, R. C. Stoler, G. Dahle, K. A. Rein, M. Shaw, G. M. Scalia, M. Guerrero, P. Pearson, S. Kapadia, M. Gillinov, A. Pichard, P. Corso, J. Popma, M. Chuang, P. Blanke, J. Leipsic and P. Sorajja (2016). “Transcatheter Mitral Valve Replacement for Patients With Symptomatic Mitral Regurgitation: A Global Feasibility Trial.” J Am Coll Cardiol. Dec 20. pii: S0735-1097(16)37122-4. doi: 10.1016/j.jacc.2016.10.068. [Epub ahead of print]

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BACKGROUND: Symptomatic mitral regurgitation (MR) is associated with high morbidity and mortality that can be ameliorated by surgical valve repair or replacement. Despite this, many patients with MR do not undergo surgery. Transcatheter mitral valve replacement (TMVR) may be an option for selected patients with severe MR. OBJECTIVES: This study aimed to examine the effectiveness and safety of TMVR in a cohort of patients with native valve MR who were at high risk for cardiac surgery. METHODS: Patients underwent transcatheter, transapical delivery of a self-expanding mitral valve prosthesis and were examined in a prospective registry for short-term and 30-day outcomes. RESULTS: Thirty patients (age 75.6 +/- 9.2 years; 25 men) with grade 3 or 4 MR underwent TMVR. The MR etiology was secondary (n = 23), primary (n = 3), or mixed pathology (n = 4). The Society of Thoracic Surgeons Predicted Risk of Mortality was 7.3 +/- 5.7%. Successful device implantation was achieved in 28 patients (93.3%). There were no acute deaths, strokes, or myocardial infarctions. One patient died 13 days after TMVR from hospital-acquired pneumonia. Prosthetic leaflet thrombosis was detected in 1 patient at follow-up and resolved after increased oral anticoagulation with warfarin. At 30 days, transthoracic echocardiography showed mild (1+) central MR in 1 patient, and no residual MR in the remaining 26 patients with valves in situ. The left ventricular end-diastolic volume index decreased (90.1 +/- 28.2 ml/m2 at baseline vs. 72.1 +/- 19.3 ml/m2 at follow-up; p = 0.0012), as did the left ventricular end-systolic volume index (48.4 +/- 19.7 ml/m2 vs. 43.1 +/- 16.2 ml/m2; p = 0.18). Seventy-five percent of the patients reported mild or no symptoms at follow-up (New York Heart Association functional class I or II). Successful device implantation free of cardiovascular mortality, stroke, and device malfunction at 30 days was 86.6%. CONCLUSIONS: TMVR is an effective and safe therapy for selected patients with symptomatic native MR. Further evaluation of TMVR using prostheses specifically designed for the mitral valve is warranted. This intervention may help address an unmet need in patients at high risk for surgery.

Park, B. J., J. M. Snider, N. R. Bates, S. D. Cassivi, G. K. Jett, J. R. Sonett and E. M. Toloza (2016). “Prospective evaluation of biodegradable polymeric sealant for intraoperative air leaks.” J Cardiothorac Surg 11(1): 168.

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BACKGROUND: A biodegradable polymeric sealant has been previously shown to reduce postoperative air leaks after open pulmonary resection. The aim of this study was to evaluate safety and efficacy during minimally invasive pulmonary resection. METHODS: In a multicenter prospective single-arm trial, 112 patients with a median age of 69 years (range 34-87 years) were treated with sealant for at least one intraoperative air leak after standard methods of repair (sutures, staples or cautery) following minimally invasive pulmonary resection (Video-Assisted Thoracic Surgery (VATS) or Robotic-Assisted). Patients were followed in hospital and 1 month after surgery for procedure-related and device-related complications and presence of air leak. RESULTS: Forty patients had VATS and 72 patients had Robotic-Assisted procedures with the majority (80/112, 71%) undergoing anatomic resection (61 lobectomy, 13 segmentectomy, 6 bilobectomy). There were no device-related adverse events. The overall morbidity rate was 41% (46/112), with major complications occurring in 16.1% (18/112). In-hospital mortality and 30-day mortality were 1.9% (2/103). The majority of intraoperative air leaks (107/133, 81%) were sealed after sealant application, and an additional 16% (21/133) were considered reduced. Forty-nine percent of patients (55/112) were free of air leak throughout the entire postoperative study period. Median chest tube duration was 2 days (range 1 – 46 days), and median length of hospitalization was 3 days (range 1 – 20 days). CONCLUSIONS: This study demonstrated that use of a biodegradable polymer for closure of intraoperative air leaks as an adjunct to standard methods is safe and effective following minimally invasive pulmonary resection.

Szerlip, M. (2016). “Transcatheter aortic valve replacement: Only one of the advantages of being female.” J Am Coll Cardiol 68(25): 2745-2746.

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Female sex has been an independent predictor of worse outcomes after surgical aortic valve replacement (SAVR). Over the past decade, transcatheter aortic valve replacement (TAVR) has become the standard of care for treatment of severe symptomatic aortic stenosis in high-risk and inoperable patients. In contradistinction to the SAVR data, TAVR outcomes data from the initial pivotal randomized trials and sponsor’s post-approval registries have shown a survival benefit for female patients compared with male patients. This benefit occurs despite higher periprocedural vascular and bleeding complication rates in female patients. The exact reasons as to why female sex in TAVR confers a survival benefit compared with male sex, especially when it is diametrically the opposite of SAVR, have yet to be determined 1, 2, 3 and 4.

Vasudevan, A., T. Bottiglieri, K. M. Tecson, M. Sathyamoorthy, J. M. Schussler, C. E. Velasco, L. R. Lopez, C. Swift, M. Peterson, J. Bennett-Firmin, R. Schiffmann and P. A. McCullough (2016). “Residual thromboxane activity and oxidative stress: Influence on mortality in patients with stable coronary artery disease.” Coron Artery Dis: 2016 Dec [Epub ahead of print].

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BACKGROUND: Aspirin use is effective in the prevention of cardiovascular disease; however, not all patients are equally responsive to aspirin. Oxidative stress reflected by F2-isoprostane [8-iso-prostaglandin-F2alpha (8-IsoPGF2alpha)] is a potential mechanism of failure of aspirin to adequately inhibit cyclooxygenase-1. The objective was to examine the relation between all-cause mortality and the concentrations of urinary 11-dehydro thromboxane B2 (11dhTxB2) and 8-IsoPGF2alpha in patients with stable coronary artery disease (CAD). METHODS: The data for this analysis are from a prospective study in which patients were categorized into four groups based on the median values of 11dhTxB2 and 8-IsoPGF2alpha. RESULTS: There were 447 patients included in this analysis with a median (range) age of 66 (37-91) years. The median (range) values of 11dhTxB2 and 8-IsoPGF2alpha were 1404.1 (344.2-68296.1) and 1477.9 (356.7-19256.3), respectively. A total of 67 (14.9%) patients died over a median follow-up of 1149 days. The reference group for the Cox proportional hazards survival analysis was patients with values of 11dhTxB2 and 8-IsoPGF2alpha below their corresponding medians. Adjusting for the age and sex, patients with values of 11dhTxB2 greater than the median had a significantly higher risk of mortality when compared with the reference group (high 11dhTxB2 and low 8-IsoPGF2alphaadj: hazard ratio: 3.2, 95% confidence interval: 1.6-6.6, P=0.002; high 11dhTxB2 and 8-IsoPGF2alphaadj: hazard ratio: 3.6, 95% confidence interval: 1.8-7.3, P<0.001). The findings were similar when we adjusted for the comorbidities of cancer, kidney function, and ejection fraction. CONCLUSION: We found that 11dhTxB2 appears to be a better prognostic marker for mortality as compared with 8-IsoPGF2alpha, suggesting aspirin resistance itself is a stronger independent determinant of death in CAD patients treated with aspirin.

Zile, M. R., B. L. Claggett, M. F. Prescott, J. J. McMurray, M. Packer, J. L. Rouleau, K. Swedberg, A. S. Desai, J. Gong, V. C. Shi and S. D. Solomon (2016). “Prognostic implications of changes in n-terminal pro-b-type natriuretic peptide in patients with heart failure.” J Am Coll Cardiol 68(22): 2425-2436.

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BACKGROUND: Natriuretic peptides (NP) have prognostic value in heart failure (HF), although the clinical importance of changes in NP from baseline is unclear. OBJECTIVES: The authors assessed whether a reduction in N-terminal pro-B-type NP (NT-proBNP) was associated with a decrease in HF hospitalization and cardiovascular mortality (primary endpoint) in patients with HF and reduced ejection fraction, whether treatment with sacubitril/valsartan reduced NT-proBNP below specific partition values more than enalapril, and whether the relationship between changes in NT-proBNP and changes in the primary endpoint were dependent on assigned treatment. METHODS: In PARADIGM-HF (Prospective Comparison of ARNI [Angiotensin Receptor-Neprilysin Inhibitor] with ACEI [Angiotensin-Converting-Enzyme Inhibitor] to Determine Impact on Global Mortality and Morbidity in Heart Failure Trial), baseline NT-proBNP was measured in 2,080 patients; 1,292 had baseline values >1,000 pg/ml and were reassessed at 1 and 8 months. We related change in NT-proBNP to outcomes. RESULTS: One month after randomization, 24% of the baseline NT-proBNP levels 1,000 pg/ml had fallen to /=1,000 pg/ml. Risk of the primary endpoint was 59% lower in patients with a fall in NT-proBNP to /=1,000 pg/ml than in those without such a fall. In sacubitril/valsartan-treated patients, median NT-proBNP was significantly lower 1 month after randomization than in enalapril-treated patients, and it fell to =1,000 pg/ml in 31% versus 17% of patients treated with sacubitril/valsartan and enalapril, respectively. There was no significant interaction between treatment and the relationship between change in NT-proBNP and the subsequent risk of the primary endpoint. CONCLUSIONS: Patients who attained a significant reduction in NT-proBNP had a lower subsequent rate of cardiovascular death or HF hospitalization independent of the treatment group. Treatment with sacubitril/valsartan was nearly twice as likely as enalapril to reduce NT-proBNP to values /=1,000 pg/ml. (Prospective Comparison of ARNI [Angiotensin Receptor-Neprilysin Inhibitor] with ACEI [Angiotensin-Converting-Enzyme Inhibitor] to Determine Impact on Global Mortality and Morbidity in Heart Failure Trial)