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Clinical decision-making that best serves the interests of our patients requires the synthesis of evidence-based medicine, sound clinical judgment and guidelines. However, a relatively low percentage of clinical guidelines are based on well-designed prospective randomized clinical trials. Thus the foundation on which good clinical outcomes can be reasonably expected should be based on i) data derived from the most applicable and highest quality clinical studies available, and ii) 'tried and tested' clinical maxims acquired through experience that are, in turn, those ideas that are in keeping with a reasonable body of medical opinion. It follows that poor decision-making and unfavorable clinical outcomes can be linked to inappropriate or inferior quality evidence, or incorrectly conceived or implemented clinical judgment. Here we review selected areas of recent controversy in clinical cardiology, highlighting the critical role of evidence-based medicine when making informed clinical decisions to help avoid harm in our patients., Competing Interests: Declaration of Competing Interest All authors have no conflicts of interest or competing interests to disclose., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Background: Coronary microvascular dysfunction (CMD) is linked to adverse cardiovascular events. Definitive diagnosis of CMD requires invasive provocative testing during angiography. We developed and tested a novel computerized T wave analysis tool to identify electrocardiographic signatures of CMD., Methods: 1552 patients underwent an invasive assessment of coronary microvascular function. Patients with interpretable pre-procedural ECGs were divided into 2 age and sex matched groups (n=261 in each group, 75% female): normal microvascular function, CFR>2.5 (CFR+), and abnormal microvascular function, CFR ≤ 2.5 (CFR-). ECGs were evaluated using a novel T wave program that quantified subtle changes in T wave morphology., Results: T wave repolarization parameters were significantly different between patients with normal and abnormal microvascular function. The top 3 features in males comprised of T wave area in V6 (CFR+: 10091.4 mV(2) vs. CFR-: 8152.3 mV(2), p<0.05); T1 Y-center of gravity in lead II (CFR+: 17.8 mV vs. CFR-: 22.4, p<0.005) and T Peak-T End in lead II (CFR+: 97.6 msec vs. CFR-: 91.1 msec, p<0.05). These could identify the presence of an abnormal CFR with 74 ± 0.2% accuracy. In females, the top 3 features were T wave right slope lead V6 (CFR+: -2489.1 mV/msec vs. CFR-: -2352.3 mV/msec, p<0.005); Amplitude in V6 (CFR+: 190.4 mV vs. 172.7 mV, p=0.05) and Y-center of gravity in lead V1 (CFR+: 33.3 vs. CFR-: 40.0, p=0.001). These features could identify the presence of an abnormal CFR with 67 ± 0.3% accuracy., Conclusion: Our data demonstrates that a computer-based repolarization measurement tool may identify electrocardiographic signatures of CMD., (Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.)

Background: Skeletal muscle atrophy contributes to increased afferent feedback (group III and IV) and may influence ventilatory control (high VE/VCO2 slope) in heart failure (HF)., Objective: This study examined the influence of muscle mass on the change in VE/VCO2 with afferent neural block during exercise in HF., Methods: 17 participants [9 HF (60±6 yrs) and 8 controls (CTL) (63±7 yrs, mean±SD)] completed 3 sessions. Session 1: dual energy x-ray absorptiometry and graded cycle exercise to volitional fatigue. Sessions 2 and 3: 5 min of constant-work cycle exercise (65% of peak power) randomized to lumbar intrathecal injection of fentanyl (afferent blockade) or placebo. Ventilation (VE) and gas exchange (oxygen consumption, VO2; carbon dioxide production, VCO2) were measured., Results: Peak work and VO2 were lower in HF (p<0.05). Leg fat was greater in HF (34.4±3.0 and 26.3±1.8%) and leg muscle mass was lower in HF (63.0±2.8 and 70.4±1.8%, respectively, p<0.05). VE/VCO2 slope was reduced in HF during afferent blockade compared with CTL (-18.8±2.7 and -1.4±2.0%, respectively, p=0.02) and was positively associated with leg muscle mass (r2=0.58, p<0.01) and negatively associated with leg fat mass (r2=0.73, p<0.01) in HF only., Conclusions: HF patients with the highest fat mass and the least leg muscle mass had the greatest improvement in VE/VCO2 with afferent blockade with leg fat mass being the only predictor for the improvement in VE/VCO2 slope. Both leg muscle mass and fat mass are important contributors to ventilatory abnormalities and strongly associated to improvements in VE/VCO2 slope with locomotor afferent inhibition in HF., (Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.)