Learning curve predictors for minimally invasive mitral valve surgery; how far should the rabbit hole go?

OBJECTIVE: To analyze predictors that influence the learning curve of minimally invasive mitral valve surgery (MIMVS). METHODS: Patients who underwent MIMVS between March 2010 to March 2015 were retrospectively analyzed. Predictive factors that influence the learning curve were analyzed. RESULTS: One hundred and five patients were included in the analysis. Cardiopulmonary bypass (CPB) time in minutes was 158.72 ± 40.98 and the aortic cross-clamp (ACC) time in minutes was 114.48 ± 27.29. There were three operative mortalities, one stroke and five >2+ mitral regurgitation. ACC time in minutes was higher in the low logistic Euroscore II (LES) group (LES < 5% = 118.42 ± 27.94) versus (LES ≥ 5 = 88.66 ± 22.26), P < .05 while creatinine clearance in µmol/L was higher in the LES < 5% group (LES < 5% = 84.32 ± 33.7) versus (LES ≥ 5% = 41.66 ± 17.14), (P < .05). One patient from each group required chest tube insertion for pleural effusion P < .05. The cumulative sum analysis (CUSUM) for the first 25 patients had CPB and ACC times that reached the upper limits. Between 25 to 64 patients the curve remained stable while with the introduction of reoperations and complex surgical procedures the CUSUM reached the upper limits. CONCLUSIONS: The learning curve is affected by many factors but this should not desist surgeons from approaching this technique. The introduction of high-risk patients in clinical practice should be carefully measured based on surgeon experience.

Valve Repair in Aortic Insufficiency: A State-of-the-art Review.

Aortic valve insufficiency (AI) describes the pathology of blood leaking through the aortic valve to the left ventricle during diastole and is classified as mild, moderate or severe according to the volume of regurgitating blood. Intervention is required in severe AI when the patient is symptomatic or when the left ventricular function is impaired. Aortic valve replacement has been considered the gold standard for decades for these patients, but several repair techniques have recently emerged that offer exceptional stability and long-term outcomes. The appropriate method of repair is selected based on the mechanism of AI and each patient's anatomic variations. This review aims to describe different pathologies of AI based on its anatomy, along with the different surgical techniques of aortic repair and their reported results.

Genetic variability on adiponectin gene affects myocardial infarction risk: the role of endothelial dysfunction.

BACKGROUND: Adiponectin is an adipokine with an important role in cardiovascular system conferring anti-inflammatory and anti-atherogenic effects. Two common single nucleotide polymorphisms (SNP) on adiponectin gene, rs2241766 and rs1501299, have been associated with insulin resistance and diabetes mellitus risk however their effects on cardiovascular risk remain unclear. We examined the impact of rs2241766 and rs1501299 on circulating adiponectin levels, endothelial function and cardiovascular disease risk. METHODS: We recruited in total 594 subjects; 462 patients with angiographically confirmed coronary artery disease (CAD) and 132 controls matched for age and gender. rs2241766 and rs1501299 were genotyped by polymerase chain reaction and restriction endonuclease digestion. Serum adiponectin levels were determined by enzyme-linked immunosorbent assay. Endothelial function was assessed by the flow mediated dilatation (FMD) of the brachial artery. RESULTS: rs2241766 had no effects on circulating adiponectin levels or FMD. In subjects without CAD, carriers of the T/T alleles at rs1501299 had lower adiponectin levels (p=0.001) and impaired endothelial function (p<0.05). After multivariate adjustment none of the SNPs had any effect on CAD risk. However, carriers of the T allele at rs1501299 were at increased myocardial infarction (MI) risk, independently of classic risk factors (OR=2.558 [95%CI=1.587-4.123], p=0.0001). The number of T alleles in both SNPs was strongly associated with MI history (p=0.0001). CONCLUSIONS: rs1501299 polymorphism of adiponectin gene affects circulating adiponectin levels and endothelial function in subjects without CAD. Presence of the T variant at rs1501299 on adiponectin gene is independently associated with increased myocardial infarction risk.