David D. Shin

Improvement in hyponatremia during hospitalization for worsening heart failure is associated with improved outcomes: insights from the Acute and Chronic Therapeutic Impact of a Vasopressin Antagonist in Chronic Heart Failure (ACTIV in CHF) trial

Background: Hyponatremia predicts poor outcome in patients with acute heart failure syndromes. This study evaluated the relationship between baseline serum sodium, change in serum sodium, and 60‐day mortality in hospitalized heart failure patients. Methods: A post‐hoc analysis of the ACTIV in CHF trial was performed. ACTIV in CHF randomized 319 patients hospitalized for worsening heart failure to placebo or one of three tolvaptan doses. Cox proportional hazards regression‐analysis was used to explore the relationship between baseline hyponatremia, sodium change during the hospitalization, and 60‐day mortality. Results: Hyponatremia was observed in 69 patients (21.6%). After covariate adjustment, baseline hyponatremia was a statistically significant predictor of 60‐day mortality (P = 0.0016). Follow‐up serum sodium data were available in 68 patients. At hospital discharge, 45 of 68 (66.2%) hyponatremic patients had improvements in serum sodium levels (⩾2 mmol/l). Hyponatremic patients with a serum sodium improvement had a mortality rate of 11.1% at 60 days post discharge, compared with a 21.7% mortality rate in those showing no improvement. After covariate adjustment, change in serum sodium was a statistically significant predictor of 60‐day mortality (HR: 0.736, 95% CI: 0.569–0.952 for each 1‐mmol/l increase in serum sodium from baseline). Conclusions: Serum sodium improvements during hospitalization for heart failure were associated with improved survival at 60 days.

Early pharmacological treatment of acute heart failure syndromes: A systematic review of clinical trials

Context: Acute Heart Failure Syndromes (AHFS) is a common admission diagnosis associated with high mortality and hospital readmissions. Given the mixed results of recent clinical trials, the early management of AHFS remains controversial. Objective: To review the recent evidence regarding current and investigational therapies for the early management of AHFS. Data Sources: A systematic search of peer‐reviewed publications was performed on MEDLINE and EMBASE from January 1990 to August 2006. The results of unpublished or ongoing trials were obtained from presentations at national and international meetings and pharmaceutical industry releases. Bibliographies from these references were also reviewed, as were additional articles identified by content experts. Study Selection and Data Extraction: Criteria used for study selection were controlled study design, relevance to clinicians and validity based on venue of publication and power analysis. Data Synthesis: Although all current intravenous therapies for the early management of AHFS appear to improve hemodynamics, this may not always translate into short‐term clinical benefit. Conclusion: The results of the trials conducted to date in AHFS have generally been disappointing. There is, therefore, an unmet need for new therapeutic approaches for the early management of AHFS that may improve the short‐term and long‐term outcomes.

Are the American College of Cardiology/Emergency Cardiac Care (ACC/ECC) guidelines useful in triaging patients to telemetry units?

Purpose: To determine if the ACC/ECC guidelines (1991) properly stratify patients according to risk of arrhythmia, defined as a single event on cardiac monitoring, and benefit, defined as a subsequent management change from a recorded telemetry event. Subjects and Methods: In 2003, a prospective study of 217 consecutive patients admitted to a 24‐bed telemetry unit was conducted for 25 days at a major academic hospital. Patients were categorized per ACC/ECC guidelines as appropriate (class I & II) or inappropriate (class III) based on a non‐cardiologist admission diagnosis. A cardiologist‐led group then reclassified patients at the time of admission using a brief interview. Continuous telemetry‐recorded arrhythmias and resultant management changes were reviewed and recorded daily. Subgroup analysis of patients admitted with a chief complaint of chest pain was also performed. In 2004, after this trial was performed, the American Heart Association released a scientific statement updating practice standards for ECG monitor; however, this paper is based upon the original 1991 ACC/ECC guidelines. Results: Reclassification significantly decreased the percentage of all class I & II patients from 91% to 71% (P<0.001) and the percentage of class I & II patients with chest pain from 100% to 58% (P<0.001) without increasing the percentage of arrhythmias occurring in class III patients. Class II patients had a statistically significant higher percentage of arrhythmias than class I and III patients before and after reclassification (P<0.001 and P<0.001, respectively). Management changes occurring as a direct result of telemetry events were higher in class II than class I or III patients before and after reclassification (P = 0.01 and P = 0.03). Life‐threatening arrhythmias (sustained ventricular tachycardia or ventricular fibrillation) occurred in 1% of the 216 patients enrolled in this study. Conclusions: (1) Cardiology input using ACC/ECC guidelines and a brief interview at admission safely reduced total admissions primarily by identifying low risk chest pain admissions inappropriate for inpatient telemetry monitoring. (2) Life threatening arrhythmias occurring in patients admitted to telemetry are rare.