Interhospital Variation in Admissions Managed With Critical Care Therapies or Invasive Hemodynamic Monitoring in Tertiary Cardiac Intensive Care Units: An Analysis From the Critical Care Cardiology Trials Network Registry.

BACKGROUND: Wide interhospital variations exist in cardiovascular intensive care unit (CICU) admission practices and the use of critical care restricted therapies (CCRx), but little is known about the differences in patient acuity, CCRx utilization, and the associated outcomes within tertiary centers. METHODS: The Critical Care Cardiology Trials Network is a multicenter registry of tertiary and academic CICUs in the United States and Canada that captured consecutive admissions in 2-month periods between 2017 and 2022. This analysis included 17 843 admissions across 34 sites and compared interhospital tertiles of CCRx (eg, mechanical ventilation, mechanical circulatory support, continuous renal replacement therapy) utilization and its adjusted association with in-hospital survival using logistic regression. The Pratt index was used to quantify patient-related and institutional factors associated with CCRx variability. RESULTS: The median age of the study population was 66 (56-77) years and 37% were female. CCRx was provided to 62.2% (interhospital range of 21.3%-87.1%) of CICU patients. Admissions to CICUs with the highest tertile of CCRx utilization had a greater burden of comorbidities, had more diagnoses of ST-elevation myocardial infarction, cardiac arrest, or cardiogenic shock, and had higher Sequential Organ Failure Assessment scores. The unadjusted in-hospital mortality (median, 12.7%) was 9.6%, 11.1%, and 18.7% in low, intermediate, and high CCRx tertiles, respectively. No clinically meaningful differences in adjusted mortality were observed across tertiles when admissions were stratified by the provision of CCRx. Baseline patient-level variables and institutional differences accounted for 80% and 5.3% of the observed CCRx variability, respectively. CONCLUSIONS: In a large registry of tertiary and academic CICUs, there was a >4-fold interhospital variation in the provision of CCRx that was primarily driven by differences in patient acuity compared with institutional differences. No differences were observed in adjusted mortality between low, intermediate, and high CCRx utilization sites.

Management and Outcomes of Cardiogenic Shock in Cardiac ICUs With Versus Without Shock Teams.

BACKGROUND: Single-center studies suggest that implementation of multidisciplinary cardiogenic shock (CS) teams is associated with improved CS survival. OBJECTIVES: The aim was to characterize practice patterns and outcomes in the management of CS across multiple centers with versus without shock teams. METHODS: The Critical Care Cardiology Trials Network is a multicenter network of cardiac intensive care units (CICUs) in North America. All consecutive medical admissions to each CICU (n = 24) were captured during annual 2-month collection periods (2017-2019; n = 6,872). Shock management and CICU mortality among centers with versus without shock teams were compared using inverse probability weighting. RESULTS: Ten of the 24 centers had shock teams. Among 1,242 CS admissions, 44% were at shock team centers. The groups were well-balanced with respect to demographics, shock etiology, Sequential Organ Failure Assessment score, biochemical markers of end organ dysfunction, and invasive hemodynamics. Centers with shock teams used more pulmonary artery catheters (60% vs 49%; adjusted odds ratio [OR]: 1.86; 95% CI: 1.47-2.35; P < 0.001), less overall mechanical circulatory support (MCS) (35% vs 43%; adjusted OR: 0.74; 95% CI: 0.59-0.95; P = 0.016), and more advanced types of MCS (53% vs 43% of all MCS; adjusted OR: 1.73; 95% CI: 1.19-2.51; P = 0.005) rather than intra-aortic balloon pumps. The presence of a shock team was independently associated with lower CICU mortality (23% vs 29%; adjusted OR: 0.72; 95% CI: 0.55-0.94; P = 0.016). CONCLUSIONS: In this multicenter observational study, centers with shock teams were more likely to obtain invasive hemodynamics, use advanced types of MCS, and have lower risk-adjusted mortality. A standardized multidisciplinary shock team approach may improve outcomes in CS.

Use of antithrombotic therapy for secondary prevention in patients with stable atherosclerotic cardiovascular disease: Insights from the COordinated National Network to Engage Cardiologists in the antithrombotic Treatment of patients with CardioVascular Disease (CONNECT-CVD) study.

BACKGROUND: Although acetylsalicylic acid is the most commonly used antithrombotic agent for the secondary prevention of cardiovascular events, residual atherothrombotic risk has prompted a guideline recommendation for the addition of dual antiplatelet therapy (DAPT) or dual pathway inhibition (DPI) in high vascular risk patients. Accordingly, the CONNECT CVD quality enhancement initiative provides a contemporary "snapshot" of the clinical features and antithrombotic management of atherosclerotic cardiovascular disease (ASCVD) patients in Canada. METHODS: Canadian cardiologists (49 cardiologists from six provinces) undertook a retrospective chart audit of 10 ASCVD patients in their outpatient practice who met the Cardiovascular Outcomes for People Using Anticoagulation Strategy-like criteria from May 2018 to April 2019. RESULTS: Of the 492 (two cardiologists provided 11 patients) enroled, average age was 70 years, 25% were female, 39% had diabetes and 20% had atrial fibrillation. Prior revascularisation was common (percutaneous coronary artery intervention 61%, coronary artery bypass graft 39%), with 31% having multivessel disease. A total of 47% of patients had a Reduction of Atherothrombosis for Continued Health bleeding score of ≥11 (~2.8% risk of serious bleeding at 2 years). Single antiplatelet therapy (SAPT) alone was most commonly used (62%), while 22% were on DAPT alone. In total, 22% were on oral anticoagulation (OAC), with 16% being on non-vitamin K oral anticoagulant alone, 5% on DPI and 1% received triple therapy. CONCLUSIONS: In contemporary Canadian clinical practice of stable ASCVD patients, a large number of patients receive antithrombotic therapy other than SAPT. Further efforts are required to guide the appropriate selection of patients in whom more potent antithrombotic therapies may safely reduce residual risk.

Troponin rise in hospitalized patients with nonacute coronary syndrome: retrospective assessment of outcomes and predictors.

BACKGROUND: Cardiac troponin is elevated in several clinical settings apart from thrombotic acute coronary syndrome (ACS) and is associated with increased adverse events. It is not clear whether troponin elevation in type II myocardial infarction (MI) is associated with increased cardiovascular events. Our objectives were to identify the cause of mortality in type II MI and to attempt to establish the threshold range of cardiac troponin-I (cTnI) elevation as well as clinical factors associated with adverse outcomes in type II MI. METHODS: This retrospective cohort study included 245 patients presenting with a noncardiac primary diagnosis associated with cTnI elevation at a single centre from January 2003 to December 2011. Primary outcome was a composite of cardiovascular and noncardiovascular mortality. Secondary outcomes included subsequent stroke, ACS, and heart failure (HF). RESULTS: At 1 year, ACS occurred in 13 patients (5.3%), stroke was seen in 10 (4.1%) patients, and HF occurred in 19 (7.8%) patients. Overall 1-year mortality included 102 events (41.6%), with 10 cardiovascular deaths (9.8%), 65 noncardiovascular deaths (63.7%), and 27 (26.5%) deaths from unknown causes. In multivariable analysis, factors independently associated with increased overall 1-year mortality included cTnI elevation ≥ 4.63 µg/L (odds ratio [OR], 3.37; 95% confidence interval [CI], 1.55-7.34; P = 0.002), age ≥ 70 years (OR, 2.44; 95% CI, 1.40-4.29; P = 0.002), and estimated glomerular filtration rate < 30 mL/min/1.73m(2) (OR, 2.40; 95% CI 1.31-4.40; P = 0.005). CONCLUSIONS: Unlike the published literature, our study includes a variety of both operative and nonoperative clinical settings associated with troponin elevation. We illustrate that although overall mortality is high after type II MI, the majority of mortality is caused by noncardiovascular events.

Effect of exercise training on pulmonary oxygen uptake kinetics in heart transplant recipients.

Pulmonary oxygen uptake (V˙O2p) at exercise onset is severely delayed in heart transplant recipients (HTRs). The role of exercise training to improve V˙O2p kinetics in HTRs has not been studied. We examined V˙O2p kinetics before and after 12 weeks of aerobic and strength training (HTR-T; n = 19, mean ± SD age: 57 ± 10 years) or usual care (HTR-UC; n = 16, mean age: 58 ± 12 years). Phase II V˙O2p kinetics, reflecting the rate of muscle metabolic adaptation, improved 37% after training compared with usual care (HTR-UC, 15 ± 19 vs 2 ± 13 seconds improvement, p = 0.02). The change in rest to steady-state heart rate reserve before and after 12 weeks was not different in HTR-T (-2 ± 9 beats/min) and HTR-UC (-1 ± 7 beats/min; p = 0.78). No significant relation was found between the change in V˙O2p kinetics and rest to steady-state heart rate reserve. Changes in leg lean tissue mass and V˙O2p kinetics were significantly related (r = -0.46, p = 0.008). In conclusion, a favorable adaptation in skeletal muscle oxidative function may underpin our finding of faster V˙O2p kinetics in HTRs after exercise training.

Forced euvolemic diuresis with mannitol and furosemide for prevention of contrast-induced nephropathy in patients with CKD undergoing coronary angiography: a randomized controlled trial.

BACKGROUND: Contrast-induced nephropathy is common in patients with coronary angiography. Mechanistically, forced euvolemic diuresis with mannitol and furosemide ought to prevent contrast-induced nephropathy. Our objectives are to: (1) undertake a randomized trial testing this hypothesis, and (2) conduct a meta-analysis of our findings with 2 earlier studies. STUDY DESIGN: (1) Randomized allocation-concealed controlled trial with blinded ascertainment of outcomes, and (2) random-effects meta-analysis of 3 trials. SETTING & PARTICIPANTS: Single-center study of consenting adults with serum creatinine level greater than 1.7 mg/dL undergoing coronary angiography; patients unable to tolerate fluid challenge or receiving dialysis were excluded. Two previous trials had randomly assigned 159 patients. INTERVENTION: Forced euvolemic diuresis with saline, mannitol, and furosemide compared with saline hydration controls. All patients were pretreated with at least 500 mL of half-normal saline before angiography; during and 8 hours after, urine output was replaced milliliter per milliliter with half-normal saline. OUTCOMES & MEASUREMENTS: The primary outcome was contrast-induced nephropathy within 48 hours of the procedure, defined as a 0.5-mg/dL absolute or 25% relative increase in creatinine level. RESULTS: Overall, 92 patients were allocated to intervention (n = 46) or control (n = 46). Mean age was 64 +/- 14 (SD) years, 23% were women, 37% had diabetes, 47% used oral furosemide, mean creatinine level was 2.8 +/- 1.6 mg/dL, and most patients (72%) underwent diagnostic catheterization. Patients had a net positive fluid balance (389 +/- 958 mL for intervention versus 655 +/- 982 mL for controls; P = 0.2). Contrast-induced nephropathy occurred in 23 (50%) intervention patients versus 13 (28%) controls (relative risk, 1.77; 95% confidence interval, 1.03 to 3.05; P = 0.03; adjusted odds ratio, 3.73; P = 0.03). Within 48 hours, creatinine level had increased by 0.8 +/- 1.1 mg/dL with intervention versus 0.2 +/- 0.6 mg/dL for controls (P = 0.002). Overall, 11 (12%) patients died or required dialysis, with no difference according to allocation status (P = 0.5). Random-effects meta-analysis of published data (3 trials; 251 patients) suggests furosemide-based interventions lead to significant harm compared with hydration: pooled relative risk, 2.15; 95% confidence interval, 1.37 to 3.37; I(2) = 0%. LIMITATIONS: Small single-center study that cannot determine whether harms were related to furosemide, mannitol, or a combination. CONCLUSIONS: Forced euvolemic diuresis led to a significantly increased risk of contrast-induced nephropathy. This strategy should be abandoned, and our results suggest that oral furosemide therapy perhaps should be held before angiography.

Triggering of the Bezold Jarisch Reflex by reperfusion during primary PCI with maintenance of consciousness by cough CPR: a case report and review of pathophysiology.

This report documents a case of hemodynamic collapse during primary angioplasty (PCI) for acute inferior ST-segment elevation myocardial infarction (STEMI). The patient had stable vital signs during the initial angiogram which had demonstrated an occluded mid right coronary artery (RCA). There was no evidence of right ventricular infarction or heart block. Reperfusion arrhythmia did not occur. The case illustrates triggering of the Bezold Jarisch Reflex (BJR) not by occlusion but reperfusion. In addition, this report illustrates the use of cough cardiopulmonary resuscitation (cough-CPR) to maintain consciousness during the BJR. Cough-CPR has previously been reported as a temporizing mechanism during ventricular arrhythmia prior to electrical cardioversion. This primary PCI case puts into clinical context the findings of historical animal studies and compares with clinical observations made during trials of intracoronary thrombolytic therapy.

Impaired pulmonary oxygen uptake kinetics and reduced peak aerobic power during small muscle mass exercise in heart transplant recipients.

We examined peak and reserve cardiovascular function and skeletal muscle oxygenation during unilateral knee extension (ULKE) exercise in five heart transplant recipients (HTR, mean +/- SE; age: 53 +/- 3 years; years posttransplant: 6 +/- 4) and five age- and body mass-matched healthy controls (CON). Pulmonary oxygen uptake (Vo(2)(p)), heart rate (HR), stroke volume (SV), cardiac output (Q), and skeletal muscle deoxygenation (HHb) kinetics were assessed during moderate-intensity ULKE exercise. Peak exercise and reserve Vo(2)(p), Q, and systemic arterial-venous oxygen difference (a-vO(2diff)) were 23-52% lower (P < 0.05) in HTR. The reduced Q and a-vO(2diff) reserves were associated with lower HR and HHb reserves, respectively. The phase II Vo(2)(p) time delay was greater (HTR: 38 +/- 2 vs. CON: 25 +/- 1 s, P < 0.05), while time constants for phase II Vo(2)(p) (HTR: 54 +/- 8 vs. CON: 31 +/- 3 s), Q (HTR: 66 +/- 8 vs. CON: 28 +/- 4 s), and HHb (HTR: 27 +/- 5 vs. CON: 13 +/- 3 s) were significantly slower in HTR. The HR half-time was slower in HTR (113 +/- 21 s) vs. CON (21 +/- 2 s, P < 0.05); however, no significant difference was found between groups for SV kinetics (HTR: 39 +/- 8 s vs. CON 31 +/- 6 s). The lower peak Vo(2)(p) and prolonged Vo(2)(p) kinetics in HTR were secondary to impairments in both cardiovascular and skeletal muscle function that result in reduced oxygen delivery and utilization by the active muscles.

Percutaneous coronary intervention for extrinsic coronary compression after pulmonary valve replacement.

Coronary artery compression is a rare and potentially fatal complication after pulmonary valve replacement. This report describes myocardial infarction from extrinsic left main coronary artery compression after pulmonary valve replacement in a 10-y-old boy. He was successfully treated with percutaneous coronary intervention.

Supratherapeutic response to ezetimibe administered with cyclosporine.

OBJECTIVE: To report the case of a patient who underwent orthotopic heart transplant (OHT) and demonstrated a supratherapeutic response to ezetimibe when administered with cyclosporine. CASE SUMMARY: Ezetimibe 10 mg/day was added to the lipid-lowering regimen (atorvastatin 40 mg/day) of a 64-year-old male patient after OHT to achieve a target low-density lipoprotein cholesterol (LDL-C) level < or = 97 mg/dL, as recommended by national guidelines. After 2 months of ezetimibe, the patient's LDL-C level had decreased by 60% to 51 mg/dL. Subsequently, the dose of ezetimibe was reduced to 5 mg/day and, after another 2 months, a repeat lipid panel revealed LDL-C 57 mg/dL. DISCUSSION: Hyperlipidemia is a common problem among heart transplant recipients. Combination therapy using a statin plus ezetimibe appears to be an attractive option to achieve target lipid levels in this population. However, the manufacturer warns that ezetimibe should be administered cautiously in patients concomitantly receiving cyclosporine. Unpublished data suggest a pharmacokinetic interaction between ezetimibe and cyclosporine that results in a significant 2.3- to 12-fold increase in exposure to total ezetimibe. An objective causality assessment in this case revealed that this supratherapeutic LDL-C reduction was probably related to coadministration of ezetimibe and cyclosporine. A potential mechanism to explain this interaction might be an alteration in glucuronidation induced by cyclosporine. CONCLUSIONS: When ezetimibe is prescribed for patients concomitantly receiving cyclosporine, it should be initiated at a lower than recommended dose (> or = 5 mg/day) and titrated upward. Careful and consistent monitoring of patients on this combination is also advised.

Do cardiac troponins provide prognostic insight in hemodialysis patients?

BACKGROUND: The diagnosis of myocardial necrosis in patients with chronic renal failure is often difficult because biochemical markers of cardiac damage such as creatine kinase MB (CKMB) and cardiac troponin T (cTnT) may be spuriously elevated. Recent small studies also report unexplained elevations in cardiac troponin I (cTnI) in chronic renal failure patients undergoing hemodialysis. The relative incidence of elevated cardiac troponins in this population and their relationship to clinical events remain unknown. OBJECTIVE: To determine the incidence and prognostic significance of asymptomatic elevations of cTnT and cTnI in patients undergoing hemodialysis for chronic renal failure. DESIGN: Prospective cohort study. SETTING: University tertiary care teaching hospital. PATIENTS: One hundred thirteen patients over 21 years of age undergoing onsite hemodialysis were enrolled between December 1997 and February 1998. MEASUREMENTS: All-cause and cardiovascular mortality, hospitalization for acute myocardial infarction, unstable angina or congestive heart failure, new onset sustained arrhythmia or need for unscheduled emergency hemodialysis due to volume overload at 30 days and six months. RESULTS: The incidence of abnormal results for cTnT, cTnI and CKMB were 42%, 15% and 4%, respectively. Independent predictors of mortality at six months were median age greater than 63 years (odds ratio 14.3, 95% CI 1.5 to 130.3, P=0.019) and positive cTnT (odds ratio 13.6, 95% CI 2.5 to 73.2, P=0.002). Diabetics were more likely to have positive cTnI and cTnT results than nondiabetics (P<0.001 and P=0.023, respectively). CONCLUSIONS: cTnT is commonly elevated in patients with chronic renal failure even in the absence of acute coronary syndromes. cTnT may be an important independent prognostic marker in patients on hemodialysis for chronic renal failure. While less common, elevations of cTnI are more frequent than CKMB elevations. The basis of these cardiac troponin elevations is unclear. These findings may represent, in part, a subclinical myocardial injury, an inflammatory response to chronic renal failure or a chronically volume overloaded state.