Cardioversion of atrial fibrillation in obese patients: Results from the Cardioversion-BMI randomized controlled trial.

AIMS: Obesity is associated with higher electrical cardioversion (ECV) failure in persistent atrial fibrillation (PeAF). For ease-of-use, many centers prefer patches over paddles. We assessed the optimum modality and shock vector, as well as the safety and efficacy of the Manual Pressure Augmentation (MPA) technique. METHODS: Patients with obesity (BMI ≥ 30) and PeAF undergoing ECV using a biphasic defibrillator were randomized into one of four arms by modality (adhesive patches or handheld paddles) and shock vector (anteroposterior [AP] or anteroapical [AA]). If the first two shocks (100 and 200 J) failed, then patients received a 200-J shock using the alternative modality (patch or paddle). Shock vector remained unchanged. In an observational substudy, 20 patients with BMI of 35 or more, and who failed ECV at 200 J using both patches/paddles underwent a trial of MPA. RESULTS: In total, 125 patients were randomized between July 2016 and March 2018. First or second shock success was 43 of 63 (68.2%) for patches and 56 of 62 (90.3%) for paddles (P = 0.002). There were 20 crossovers from patches to paddles (12 of 20 third shock success with paddles) and six crossovers from paddles to patches (three of six third shock success with patches). Paddles successfully cardioverted 68 of 82 patients compared with 46 of 69 using patches (82.9% vs 66.7%; P = 0.02). Shock vector did not influence first or second shock success rates (82.0% AP vs 76.6% AA; P = 0.46). MPA was successful in 16 of 20 (80%) who failed in both (patches/paddles), with 360 J required in six of seven cases. CONCLUSION: Routine use of adhesive patches at 200 J is inadequate in obesity. Strategies that improve success include the use of paddles, MPA, and escalation to 360 J.

Comparison of short-term clinical outcomes of proximal versus nonproximal lesion location in patients treated with primary percutaneous coronary intervention for ST-elevation myocardial infarction: The PROXIMITI study.

OBJECTIVES: The objective of this study was to investigate the association of proximal and nonproximal location of culprit coronary lesions with clinical outcomes of patients presenting with ST-elevation myocardial infarction (STEMI) treated by primary percutaneous coronary intervention (PCI). BACKGROUND: Proximal culprit lesion location in patients presenting with STEMI is associated with increased mortality when compared to distal culprit lesions in the thrombolytic era. The impact of lesion location on clinical outcomes in the era of PCI remains unclear. METHODS: We analyzed 3,283 patients with STEMI who enrolled in the Victorian Cardiac Outcomes Registry. We compared outcomes in those with proximal lesion location versus patients with nonproximal location. RESULTS: Of 3,283 participants, 1,376 (41.9%) had a proximal lesion location. Patients with proximal lesion location presented with greater rates of cardiogenic shock and out-of-hospital cardiac arrest, and left ventricular systolic dysfunction, all P < .01. Procedural success rates were similar (96% vs. 95%, P = .08). Patients with proximal lesion location had higher rates of in-hospital and 30-day mortality, major adverse cardiac events (MACE; mortality, myocardial infarction, stent thrombosis, and unplanned revascularization) and major adverse cardiac and cerebrovascular events (MACCE; MACE, and stroke) compared to the nonproximal group, all P < .001. However, on multivariable regression analysis, proximal lesion location was not independently associated with MACE during in-hospital stay or at 30-days (OR 1.32, 95% CI 0.95-1.83, P = .09 and OR 1.23, 95% CI 0.92-1.65, P = .15) respectively. CONCLUSIONS: Patients with proximal lesion location had greater hemodynamic instability and higher-risk features; however, proximal lesions per se were not independently associated with worse clinical outcomes compared to nonproximal lesions.

Changes in Statin Prescription Patterns in Patients Admitted to an Australian Geriatric Subacute Unit.

BACKGROUND: Assessment of demographic and clinical factors influencing the decision of statin discontinuation in the elderly population admitted to subacute geriatric unit. The aim of this study is to assess the clinical factors impacting the decision-making process of statin discontinuation in the elderly. METHODS: We retrospectively assessed changes in statin discontinuation and prescription among patients (≥60 years old) discharged from a geriatric evaluation and management unit by reviewing hospital digital medical records at Western Health - The Williamstown Hospital over a 12-month period from 4 February 2012 until 4 February 2013 inclusive. The main outcome of the study was to determine the independent predictors of statin discontinuation using logistic regression analysis. RESULTS: Of the studied population, 46% were already prescribed statins prior to their admission. Statins were discontinued in 17.5% of patients at discharge. Predictors of statin de-prescription included octogenarian status, primary prevention indication, poor functional recovery, residential care facility discharge destination and lower cognitive function. The presence of previous cardiovascular disease history and the burden of comorbidities were not predictors of statin discontinuation. CONCLUSIONS: We observed that factors that conveyed poor prognosis such as advanced age, poor functional recovery, worse cognitive function, being discharged to a residential care facility as well as primary prevention indication for statin prescription are predictors of statin discontinuation in the geriatric unit.

Synchronous cardiac arrest in monozygotic twins with hypertrophic cardiomyopathy--is sudden cardiac death genetically pre-programmed?

BACKGROUND: Hypertrophic cardiomyopathy (HCM) is a myocardial disorder characterised by left ventricular hypertrophy (LVH) in the absence of another cardiac or systemic disease capable of producing the magnitude of LVH evident. HCM causes variable symptoms and is one of the leading causes of sudden cardiac death (SCD) in young adults. While various phenotypic features of HCM among monozygotic twin pairs are not uncommonly reported, occurrence of synchronous cardiac arrest among them is not known from literature. CASE PRESENTATION: We present a case of monozygotic twins with HCM who both had a cardiac arrest post physical exertion in 63rd year of their lives. CONCLUSION: This case highlights potential genetics predisposition of cardiac arrest in patients with HCM despite having different phenotypic expression. SCD may be the only manifestation of patients with HCM. Decision of implantable cardioverter-defibrillator (ICD) placement for primary prevention of SCD should be based on the recommended guidelines, clinical judgment and patient's preference.

Automated Assessment of Cardiac Systolic Function From Coronary Angiograms With Video-Based Artificial Intelligence Algorithms.

Importance: Understanding left ventricular ejection fraction (LVEF) during coronary angiography can assist in disease management. Objective: To develop an automated approach to predict LVEF from left coronary angiograms. Design, Setting, and Participants: This was a cross-sectional study with external validation using patient data from December 12, 2012, to December 31, 2019, from the University of California, San Francisco (UCSF). Data were randomly split into training, development, and test data sets. External validation data were obtained from the University of Ottawa Heart Institute. Included in the analysis were all patients 18 years or older who received a coronary angiogram and transthoracic echocardiogram (TTE) within 3 months before or 1 month after the angiogram. Exposure: A video-based deep neural network (DNN) called CathEF was used to discriminate (binary) reduced LVEF (≤40%) and to predict (continuous) LVEF percentage from standard angiogram videos of the left coronary artery. Guided class-discriminative gradient class activation mapping (GradCAM) was applied to visualize pixels in angiograms that contributed most to DNN LVEF prediction. Results: A total of 4042 adult angiograms with corresponding TTE LVEF from 3679 UCSF patients were included in the analysis. Mean (SD) patient age was 64.3 (13.3) years, and 2212 patients were male (65%). In the UCSF test data set (n = 813), the video-based DNN discriminated (binary) reduced LVEF (≤40%) with an area under the receiver operating characteristic curve (AUROC) of 0.911 (95% CI, 0.887-0.934); diagnostic odds ratio for reduced LVEF was 22.7 (95% CI, 14.0-37.0). DNN-predicted continuous LVEF had a mean absolute error (MAE) of 8.5% (95% CI, 8.1%-9.0%) compared with TTE LVEF. Although DNN-predicted continuous LVEF differed 5% or less compared with TTE LVEF in 38.0% (309 of 813) of test data set studies, differences greater than 15% were observed in 15.2% (124 of 813). In external validation (n = 776), video-based DNN discriminated (binary) reduced LVEF (≤40%) with an AUROC of 0.906 (95% CI, 0.881-0.931), and DNN-predicted continuous LVEF had an MAE of 7.0% (95% CI, 6.6%-7.4%). Video-based DNN tended to overestimate low LVEFs and underestimate high LVEFs. Video-based DNN performance was consistent across sex, body mass index, low estimated glomerular filtration rate (≤45), presence of acute coronary syndromes, obstructive coronary artery disease, and left ventricular hypertrophy. Conclusion and relevance: This cross-sectional study represents an early demonstration of estimating LVEF from standard angiogram videos of the left coronary artery using video-based DNNs. Further research can improve accuracy and reduce the variability of DNNs to maximize their clinical utility.

Left Ventricular End-Diastolic Pressure for the Prediction of Contrast-Induced Nephropathy and Clinical Outcomes in Patients With ST-Elevation Myocardial Infarction Who Underwent Primary Percutaneous Intervention (the ELEVATE Study).

Contrast-induced nephropathy (CIN) is an important complication of percutaneous coronary intervention (PCI). We investigated whether left ventricular end-diastolic pressure (LVEDP) in patients who underwent PCI might be additive to current risk stratification of CIN. Data from consecutive patients who underwent primary PCI for ST-elevation myocardial infarction between 2013 and 2018 at Western Health in Victoria, Australia were analyzed. CIN was defined as a 25% increase in serum creatinine from baseline or 44 µmol/L increase in absolute value within 48 hours of contrast administration. Compared with patients without CIN (n = 455, 93%), those who developed CIN (n = 35, 7%) were older (64 vs 58 years, p = 0.006), and had higher peak creatine kinase (2,862 [1,258 to 3,952] vs 1,341 U/L [641 to 2,613], p = 0.02). The CIN group had higher median LVEDP (30 [21-33] vs 25 mm Hg [20-30], p = 0.013) and higher median Mehran risk score (MRS) (5 [2-8] vs 2 [1-5], p <0.001). Patients with CIN had more in-hospital major adverse cardiovascular and cerebrovascular events (composite end point of death, new or recurrent myocardial infarction or stent thrombosis, target vessel revascularization or stroke) (23% vs 8.6%, p = 0.01), but similar 30-day major adverse cardiovascular and cerebrovascular events (20% vs 15%, p = 0.46). An LVEDP >30 mm Hg independently predicted CIN (odds ratio 3.4, 95% confidence interval 1.46 to 8.03, p = 0.005). The addition of LVEDP ≥30 mm Hg to MRS marginally improved risk prediction for CIN compared with MRS alone (area-under-curve, c-statistic = 0.71 vs c-statistic = 0.63, p = 0.08). In conclusion, elevated LVEDP ≥30 mm Hg during primary PCI was an independent predictor of CIN in patients treated for ST-elevation myocardial infarction. The addition of LVEDP to the MRS may improve risk prediction for CIN.

Rationale and Design of the Rivaroxaban Post-Transradial Access for the Prevention of Radial Artery Occlusion Trial (CAPITAL-RAPTOR).

INTRODUCTION: Transradial access (TRA) has rapidly emerged as the preferred vascular access site for coronary angiography and percutaneous coronary intervention. Radial artery occlusion (RAO) remains as an important complication of TRA as it precludes future ipsilateral transradial procedures. While intraprocedural anticoagulation has been studied extensively, the definitive role of postprocedural anticoagulation has not yet been established. METHODS AND ANALYSIS: The Rivaroxaban Post-Transradial Access for the Prevention of Radial Artery Occlusion trial is a multicentre, prospective, randomised, open-label, blinded-endpoint design study investigating the efficacy and safety of rivaroxaban to reduce the incidence of RAO. Eligible patients will undergo randomisation to receive either rivaroxaban 15 mg once daily for 7 days or to no additional postprocedural anticoagulation. Doppler ultrasound to assess radial artery patency will be performed at 30 days. ETHICS AND DISSEMINATION: The study protocol has been approved by the Ottawa Health Science Network Research Ethics Board (approval number 20180319-01H). The study results will be disseminated via conference presentations and peer-reviewed publications. TRIAL REGISTRATION NUMBER: NCT03630055.

Milrinone vs Dobutamine for the Management of Cardiogenic Shock: Implications of Renal Function and Injury.

Background: Cardiogenic shock is associated with poor clinical outcomes. There is a paucity of prospective data examining the efficacy and safety of inotropic therapy in patients with cardiogenic shock and renal dysfunction. Objectives: This study sought to examine the treatment effect of milrinone compared to dobutamine in relation to renal function. Methods: In this post hoc analysis of the DOREMI (Milrinone as Compared with Dobutamine in the Treatment of Cardiogenic Shock) trial, we examined clinical outcomes with milrinone compared to dobutamine after stratification based on baseline estimated glomerular filtration rate (eGFR) 60 ml/min/1.73 m2 and acute kidney injury (AKI). The primary outcome was the composite of in-hospital death from any cause, resuscitated cardiac arrest, receipt of a cardiac transplant or mechanical circulatory support, nonfatal myocardial infarction, transient ischemic attack or stroke, or initiation of renal replacement therapy. Results: Baseline eGFR <60 ml/min/1.73 m2 and AKI were observed in 78 (45%) and 124 (65%) of patients, respectively. The primary outcome and death from any cause occurred in 99 (52%) and 76 (40%) patients, respectively. eGFR <60 ml/min/1.73 m2 did not appear to modulate the treatment effect of milrinone compared to dobutamine. In contrast, there was a significant interaction between the treatment effect of milrinone compared to dobutamine and AKI with respect to the primary outcome (P interaction = 0.02) and death (P interaction = 0.04). The interaction was characterized by lower risk of primary outcome and death with milrinone compared to dobutamine in patients without, but not with, AKI. Conclusions: In patients requiring inotropic support for cardiogenic shock, baseline renal dysfunction and AKI are common. A modulating effect of AKI on the relative efficacy of milrinone compared to dobutamine was observed, characterized by attenuation of a potential clinical benefit with milrinone compared to dobutamine in patients who develop AKI.

Utility of a smartphone application in assessing palmar circulation prior to radial artery harvesting for coronary artery bypass grafting: rationale and design of the randomised CAPITAL iRADIAL-CABG trial.

INTRODUCTION: There is emerging evidence supporting the use of the radial artery (RA) as a preferred secondary conduit for coronary artery bypass grafting (CABG) as it is associated with higher rates of graft patency at 5 years when compared with saphenous vein grafts (SVG). The modified Allen's test (MAT) is traditionally regarded as the standard of care in the assessment of ulnar artery (UA) patency prior to RA harvesting. Unfortunately, due to high false-positive rates, a substantial number of pre-CABG patients are found to have an abnormal MAT despite normal UA patency, resulting in inappropriate exclusion from RA harvesting. The SVG is generally used in its place when this occurs, resulting in potentially lower rates of long-term graft patency. METHODS AND ANALYSIS: The CAPITAL iRADIAL-CABG trial is currently enrolling participants 18 years of age or older undergoing CABG for whom the treating physician is considering the use of an RA conduit. Eligible patients will be randomised in a 1:1 fashion to MAT or smartphone-based photoplethysmography application assessment to assess collateral palmar circulation prior to RA harvesting. The primary outcome of the trial is the use of the RA as a conduit during CABG. The primary safety outcome is postoperative palmar ischaemia as determined by clinical assessment or requirement of vascular intervention. Secondary outcomes include vascular complications, early graft failure, need for rescue percutaneous coronary intervention during the index hospitalisation and a composite cardiovascular outcome of myocardial infarction, stroke and cardiovascular death prior to discharge from hospital. A total of 236 participants are planned to be recruited. ETHICS AND DISSEMINATION: The study was approved by the Ottawa Heart Science Network Research Ethics Board (approval number 20180865-01H). The study results will be disseminated via conference presentations and peer-reviewed publications. TRIAL REGISTRATION NUMBER: NCT03810729.

Impact of atrial fibrillation on the risk of major adverse cardiac events following coronary revascularisation.

OBJECTIVE: Atrial fibrillation (AF) remains a highly prevalent arrhythmia with significant burden on morbidity and mortality. The impact of AF in the revascularised population remains incompletely described. Given the high prevalence of AF in the revascularised population, we sought to evaluate the incidence and prognosis in patients with pre-existing and new-onset AF following revascularisation. METHODS: We used the University of Ottawa Heart Institute Revascularisation Registry to identify patients who underwent revascularisation between August 2015 and March 2020, who were prospectively followed for an average of one year. We conducted a retrospective cohort study analysing the association between AF and clinical outcomes. The primary outcome of interest was 1-year major adverse cardiac events (MACE) defined as a composite of death, myocardial infarction, unplanned revascularisation and cerebrovascular accidents. Moreover, secondary outcomes include the individual components of MACE and bleeding. RESULTS: A total of 6704 patients underwent revascularisation and completed 1-year clinical follow-up. Median time to follow-up was 12.8 (IQR 11.2-15.9) months. One-year MACE occurred in 166 (21.8%) and 683 (11.5%) patients in AF and non-AF groups, respectively (adjusted HR, 1.61; 95% CI 1.29 to 2.01; p<0.0001). AF was independently predictive of 1-year mortality, myocardial infarction, unplanned revascularisation, cerebrovascular accident and bleeding. Within 1 year, 299 (4.5%) episodes of new-onset AF was observed. New-onset AF following revascularisation was also associated with 1-year MACE, mortality, myocardial infarction, cerebrovascular accident and unplanned revascularisation. CONCLUSIONS: Preprocedural and new-onset AF following revascularisation remains highly predictive 1-year MACE. AF should be considered in addition to traditional risk factors for adverse outcomes following revascularisation.

Clinical utility of exercise training in heart failure with reduced and preserved ejection fraction.

Reduced exercise tolerance is an independent predictor of hospital readmission and mortality in patients with heart failure (HF). Exercise training for HF patients is well established as an adjunct therapy, and there is sufficient evidence to support the favorable role of exercise training programs for HF patients over and above the optimal medical therapy. Some of the documented benefits include improved functional capacity, quality of life (QoL), fatigue, and dyspnea. Major trials to assess exercise training in HF have, however, focused on heart failure with reduced ejection fraction (HFREF). At least half of the patients presenting with HF have heart failure with preserved ejection fraction (HFPEF) and experience similar symptoms of exercise intolerance, dyspnea, and early fatigue, and similar mortality risk and rehospitalization rates. The role of exercise training in the management of HFPEF remains less clear. This article provides a brief overview of pathophysiology of reduced exercise tolerance in HFREF and heart failure with preserved ejection fraction (HFPEF), and summarizes the evidence and mechanisms by which exercise training can improve symptoms and HF. Clinical and practical aspects of exercise training prescription are also discussed.