Do not disregard the initial 12 lead ECG after out-of-hospital cardiac arrest: It predicts angiographic culprit despite metabolic abnormalities

Objectives

The initial 12 lead electrocardiogram (ECG) following return of spontaneous circulation (ROSC) after out-of-hospital cardiac arrest (OHCA), is often disregarded by clinicians in ability to predict acute thrombotic coronary occlusion (ATCO) due to markedly abnormal metabolic milieu (AMM). We sought to evaluate the accuracy of initial vs. follow-up ECG prior to invasive coronary angiography (ICA) to predict ATCO following resuscitated OHCA.

Methods

We included OHCA patients with initial shockable rhythm who underwent invasive coronary angiography (ICA). AMM was defined as one of: pH ​< ​7.1, lactate >2 ​mmol/L, serum potassium <2.8 or >6.0 mEq/L. Two ECGs A (initial) and B (follow-up) following ROSC but prior to ICA were adjudicated by 2 experienced readers using expanded ECG criteria to predict angiographic ATCO on ICA.

Results

152 consecutive patients (mean age 58 years, 75% male) met inclusion criteria, 77% had AMM. Among those with both ECGs (n ​= ​102), overall accuracy, sensitivity, specificity, positive predictive value, negative predictive value for correctly predicting angiographic ATCO for ECG A was 72%, 63%, 81%, 61%, 83% and for ECG B was 71%, 50%, 91%, 73%, 80% respectively. Predictive accuracy for angiographic ATCO was similar between ECG A [odds ratio (OR) 7.31, CI 2.87–18.62, p ​< ​0.0001) and ECG B [OR 10.67; CI 3.6–31.61, p ​< ​0.0001], and consistent in AMM.

Conclusions

In OHCA, despite AMM, the initial post ROSC ECG retains a statistically significant, and similar accuracy as the follow-up ECG to predict angiographic ATCO using expanded criteria.

Coronary artery calcium progresses rapidly and discriminates incident cardiovascular events in chronic kidney disease regardless of diabetes: The Multi-Ethnic Study of Atherosclerosis (MESA)

BACKGROUND AND AIMS

Chronic kidney disease (CKD) is associated with high prevalence of cardiovascular disease (CVD) events. We sought to assess the prognostic utility of coronary artery calcium (CAC) scores in discriminating incident CVD events among subpopulations of CKD, particularly those without diabetes mellitus (DM).

METHODS

Using the Multi-Ethnic Study of Atherosclerosis, we identified 4 groups based on present/absent CKD/diabetes (CKD-/DM-, n = 5308; CKD-/DM+, n = 586, CKD+/DM-, n = 620; CKD+/DM+, n = 266). Baseline and follow-up CAC (Agatston units) measurements, and association between CAC and incident CVD events in median follow-up of 13 years were evaluated using proportional hazards regression adjusting for demographics, clinical, biomarker variables.

RESULTS

Prevalence of CKD and DM in the cohort was 13% and 12.5% respectively. Annual progression in adjusted median CAC score was 24.8%, 27.9%, 26.7%, 36.8% and unadjusted cumulative incident CVD rates were 12.6%, 22.3%, 23.1%, 39.8% for CKD-/DM-, CKD-/DM+, CKD+/DM-, CKD+/DM+, respectively. After full adjustment (CKD-/DM-referent), hazard ratios (HR, 95% CI) for incident CVD events were 1.25 (1.01-1.53) CKD-/DM+, 1.10 (0.90-1.33) CKD+/DM- and 2.18 (1.73-2.76) CKD+/DM+. Using CKD-/DM-/baseline CAC = 0 referent, adjusted HRs (95% CI) for incident CVD in CKD+/DM- were 1.30 (0.81-2.07), 2.05 (1.4-2.99), and 4.15 (2.94-5.86) for baseline CAC = 0, 1-100, and >300 Agatston units respectively while for CKD+/DM+, adjusted HRs were 3.15 (2.04-4.86), 3.56 (2.26-5.62), 7.90 (5.35-11.67), respectively.

CONCLUSIONS

CAC provides incremental prognostic information to predict incident CVD events in CKD regardless of DM. Moreover, baseline CAC categories discriminate incident CVD among CKD without DM, which may have implications in individualizing approach to primary prevention in this high-risk population.

Risk Stratification and Treatment of Coronary Disease in Chronic Kidney Disease and End-Stage Kidney Disease

Patients with advanced chronic kidney disease have an enormous burden of cardiovascular morbidity and mortality, but, paradoxically, their representation in randomized trials for the evaluation and management of coronary artery disease has been limited. Clinicians therefore are faced with the conundrum of synergizing evidence from observational studies, expert opinion, and extrapolation from the general population to provide care to this complex and clinically distinct patient population. In this review, we address clinical risk stratification of patients with chronic kidney disease and end-stage kidney disease using traditional cardiovascular risk factors, noninvasive functional and structural cardiac imaging, invasive coronary angiography, and cardiovascular biomarkers. We highlight the unique characteristics of this population, including the high competing risk of all-cause mortality relative to the risk of major adverse cardiac events, likely owing to important contributions from nonatherosclerotic mechanisms. We further discuss the management of coronary artery disease in patients with chronic kidney disease and end-stage kidney disease, including evidence pertaining to medical management, coronary revascularization with percutaneous coronary intervention, and coronary artery bypass grafting. Our discussion includes considerations of drug-eluting versus bare metal stents for percutaneous coronary intervention and off-pump versus on-pump coronary artery bypass graft surgery. Finally, we address currently ongoing randomized trials, from which clinicians are optimistic about receiving guidance regarding the best strategies to incorporate into their practice for the evaluation and management of coronary artery disease in this high-risk population.

Exploring the elusive link between subclinical fibrosis and clinical events in end-stage renal disease: does cardiac magnetic resonance imaging hold the key?

Extensive myocardial fibrosis is known to occur in patients undergoing dialysis due to a variety of mechanisms not necessarily restricted to coronary artery disease. Fibrosis may predispose to reentry arrhythmias and long-term myocardial dysfunction, and sudden death and congestive heart failure are the most frequent causes of death in patients undergoing renal replacement therapy. Despite the high accuracy of magnetic resonance for imaging of myocardial fibrosis, its use has been restricted by the risk of inducing nephrogenic systemic sclerosis with the injection of gadolinium. The development of new sequences that allow the detection and quantifying of the severity of extracellular myocardial fibrosis offers a chance to study the pathogenesis of this condition and identify potential interventions to retard or reverse it. Whether these will lead to an improved outcome needs to be prospectively tested.

Non-Vitamin K-Dependent Oral Anticoagulants for Nonvalvular Atrial Fibrillation in Patients With CKD: Pragmatic Considerations for the Clinician

Management of atrial fibrillation (AF) in patients with advanced chronic kidney disease (CKD) poses a complex conundrum because of higher risks for both thromboembolic and bleeding complications compared to the general population. This makes it particularly important for clinicians to carefully weigh the risks versus benefits of anticoagulation therapy to determine the individualized net clinical benefit for every patient. During the past few years, 4 non-vitamin K-dependent oral anticoagulant (NOAC) agents have supplemented warfarin in the therapeutic armamentarium for the prevention of systemic thromboembolism in nonvalvular AF. However, the use of NOACs in CKD specifically mandates a nuanced understanding due to their varying dependence on renal clearance, with resultant safety implications related to either underdosing (thromboembolism) or excessive drug exposure (bleeding). This pragmatic review highlights unique considerations pertaining to accurate estimation and temporal monitoring of kidney function in the context of NOAC use with specific clinical deliberations and variables when determining whether an NOAC is appropriate for a patient with CKD. The dependence of NOACs on renal clearance and several troubling safety signals in the published literature suggest that it is vital for nephrologists to be active members of a multidisciplinary team caring for these high-risk patients with CKD and AF.

Trends in Discharge Claims for Acute Myocardial Infarction among Patients on Dialysis

Analysis of a contemporary cohort of patients on dialysis revealed that mortality from acute myocardial infarction (AMI) has decreased, whereas the prevalence of AMI has increased markedly, particularly among patients with non-ST elevation myocardial infarction (NSTEMI). Using inpatient discharge diagnosis codes (1993-2008), we determined that proportions of AMI claims decreased in the primary position (from 65% to 52%) but increased in the secondary position (from 35% to 48%). Proportions of NSTEMI codes increased remarkably in both the primary and secondary positions. The progressive increase in diagnostic claims for secondary AMI identifies a unique high-risk population and has important clinical, economic, and epidemiologic implications among patients on dialysis.

Infective endocarditis causing mitral valve stenosis - a rare but deadly complication: a case report

Background

Infective endocarditis rarely causes mitral valve stenosis. When present, it has the potential to cause severe hemodynamic decompensation and death. There are only 15 reported cases in the literature of mitral prosthetic valve bacterial endocarditis causing stenosis by obstruction. This case is even more unusual due to the mechanism by which functional mitral stenosis occurred.

Case presentation

We report a case of a 23-year-old white woman with a history of intravenous drug abuse who presented with acute heart failure. Transthoracic echocardiography failed to show valvular vegetation, but high clinical suspicion led to transesophageal imaging that demonstrated infiltrative prosthetic valve endocarditis causing severe mitral stenosis. Despite extensive efforts from a multidisciplinary team, she died as a result of her critical illness.

Conclusions

The discussion of this case highlights endocarditis physiology, the notable absence of stenosis in modified Duke criteria, and the utility of transesophageal echocardiography in clinching a diagnosis. It advances our knowledge of how endocarditis manifests, and serves as a valuable lesson for clinicians treating similar patients who present with stenosis but no regurgitation on transthoracic imaging, as a decision to forego a transesophageal echocardiography could cause this serious complication of endocarditis to be missed.

Electronic supplementary material

The online version of this article (doi:10.1186/s13256-017-1197-3) contains supplementary material, which is available to authorized users.

Temporal trends in ischemic stroke and anticoagulation therapy for non-valvular atrial fibrillation: effect of diabetes

BACKGROUND

Diabetes is an important risk factor for ischemic stroke in non-valvular atrial fibrillation (AF). The aim of the present study was to evaluate temporal trends in ischemic stroke and warfarin use among US Medicare patients with and without diabetes.

METHODS

In this retrospective cohort study, 1-year cohorts of patients with Medicare as the primary payer over the period 1992-2010 were created using the Medicare 5% sample (excluding patients with valvular disease and end-stage renal disease). International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes were used to identify AF, ischemic and hemorrhagic stroke, and diabetes; three or more consecutive prothrombin time claims were used to identify warfarin use.

RESULTS

Demographic characteristics of subjects in 1992 (n = 40 255) and 2010 (n = 80 314), respectively, were as follows: age 65-74 years, 37% and 32%; age >85 years, 20% and 25%; White, 94% and 93%; hypertension, 46% and 80%; diabetes, 20% and 32%; and chronic kidney disease, 5% and 18%. Among Medicare AF patients with diabetes, ischemic stroke decreased by 71% (1992-2010) from 65 to 19 per 1000 patient-years; warfarin use increased from 28% to 62%. Among patients without diabetes, ischemic stroke decreased by 68% from 44 to 14 per 1000 patient-years, whereas warfarin use increased from 26% to 59%. Approximately 38% of Medicare AF patients with diabetes did not receive anticoagulation in 2010.

CONCLUSIONS

Ischemic stroke declined and warfarin use increased similarly in Medicare patients with and without diabetes. Ischemic stroke rates were consistently higher in diabetes patients, validating the inclusion of diabetes in risk calculators. The population of Medicare patients with diabetes who did not receive warfarin deserves future attention.

Coronary Revascularization in Patients with CKD Stage 5D: Pragmatic Considerations

Coronary revascularization decisions for patients with CKD stage 5D present a dilemma for clinicians because of high baseline risks of mortality and future cardiovascular events. This population differs from the general population regarding characteristics of coronary plaque composition and behavior, accuracy of noninvasive testing, and response to surgical and percutaneous revascularization, such that findings from the general population cannot be automatically extrapolated. However, this high-risk population has been excluded from all randomized trials evaluating outcomes of revascularization. Observational studies have attempted to address long-term outcomes after surgical versus percutaneous revascularization strategies, but inherent selection bias may limit accuracy. Compared with percutaneous strategies, surgical revascularization seems to have long-term survival benefit on the basis of observational data but associates with substantially higher short-term mortality rates. Percutaneous revascularization with drug-eluting and bare metal stents associates with a high risk of in-stent restenosis and need for future revascularization, perhaps contributing to the higher long-term mortality hazard. Off-pump coronary bypass surgery and the newest generation of drug-eluting stent platforms offer no definitive benefits. In this review, we address the nuances, complexities, and tradeoffs that clinicians face in determining the optimal method of coronary revascularization for this high-risk population.

Trends in Mortality Following Acute Myocardial Infarction Among Dialysis Patients in the United States Over 15 Years

BACKGROUND

We sought to determine 15-year trends in mortality rates among dialysis patients with acute myocardial infarction (AMI) in the contemporary era.

METHODS AND RESULTS

Using the US Renal Data System database, we assembled 4 study cohorts of period-prevalent dialysis patients in 1993, 1998, 2003, and 2008 who were hospitalized for an index AMI in that calendar year. ST-segment elevation myocardial infarction (STEMI) and non-STEMI were identified, and in-hospital mortality was calculated. Cumulative probability of death during 2-year follow-up after AMI admission was estimated by the Kaplan-Meier method and adjusted for patient characteristics. A total of 42 933 dialysis patients with AMI were included. Between 1993 (n=4494) and 2008 (n=16 361), proportional increases occurred in patient groups aged ≥75 years (23% and 31%, respectively; P<0.001), of black race (25% and 31%, respectively; P<0.001), with end-stage renal disease due to diabetes (42% and 55%, respectively; P<0.001), and with non-STEMI (42.2% and 80.7%, respectively; P<0.001). For all patients with AMI, in-hospital mortality rates decreased (31.9% in 1993, 18.8% in 2008; P<0.001), as did unadjusted 2-year cumulative probability of death after AMI admission (76.5% in 1993, 71.5% in 2008; P<0.001). Between 1993 and 2008, among STEMI patients, in-hospital mortality (38.2% and 25.9%, P<0.001) and unadjusted 2-year cumulative probability of mortality (77.3% and 71.2%, P<0.001) decreased, but decreases did not occur among NSTEMI patients (14.2% and 14.9%, P=0.47, and 70.9% and 70.1%, P=0.52 respectively).

CONCLUSIONS

In-hospital mortality and 2-year cumulative probability of death following AMI among dialysis patients decreased between 1993 and 2008 but only among STEMI patients, coincident with increased in-hospital percutaneous coronary intervention rates. Period-prevalent cases of non-STEMI markedly increased without interval change in survival.

Atrial fibrillation, stroke, and anticoagulation in Medicare beneficiaries: trends by age, sex, and race, 1992-2010

BACKGROUND

We evaluated temporal trends in ischemic stroke and warfarin use among demographic subsets of the US Medicare population that are not well represented in randomized trials of warfarin for stroke prevention in nonvalvular atrial fibrillation (AF).

METHODS AND RESULTS

One-year cohorts of Medicare-primary payer patients (1992-2010) were created using the Medicare 5% sample. International Classification of Diseases, Ninth Revision, Clinical Modification codes were used to identify AF and ischemic and hemorrhagic stroke; ≥ 3 consecutive prothrombin time claims were used to identify warfarin use. Ischemic stroke rates (per 1000 patient-years) decreased markedly from 1992 to 2010. Among women, rates decreased from 37.1 to 13.6 for ages 65 to 74 years, from 55.2 to 16.5 for ages 74 to 84, and from 66.9 to 22.9 for age ≥ 85; warfarin use increased 31% to 59%, 27% to 63%, and 15% to 49%, respectively. Among men, rates decreased from 33.8 to 11.7 for ages 65 to 74 years, from 49.2 to 13.8 for ages 75 to 84, and from 51.5 to 18.0 for age ≥ 85; warfarin use increased 34% to 63%, 28% to 66%, and 15% to 55%, respectively. Rates decreased from 47.0 to 14.8 for whites and 73.0 to 29.3 for blacks; warfarin use increased 27% to 61% and 19% to 52%, respectively. In all age categories, the thromboembolic risk (CHADS [congestive heart failure, hypertension, age ≥ 75 years, diabetes, stroke]) score was significantly higher among women (versus men) and blacks (versus whites).

CONCLUSIONS

Ischemic stroke rates among Medicare AF patients decreased significantly in all demographic subpopulations from 1992-2010, coincident with increasing warfarin use. Ischemic stroke rates remained higher and warfarin use rates remained lower for women and blacks with AF, groups whose baseline CHADS scores were higher.