Prognostic indices among hypertensive heart failure patients in Nigeria: the roles of 24-hour Holter electrocardiography and 6-minute walk test

• Published in: Vascular health and risk management 2017-01, Vol.13, p.71-79
• Main Authors: Mene-Afejuku, Tuoyo O, Balogun, Michael O, Akintomide, Anthony O, Adebayo, Rasaaq A
• Format: Article
• Language: English
• Subjects: Aged; Atrial Fibrillation - diagnosis; Atrial Fibrillation - etiology; Atrial Fibrillation - mortality; Atrial Fibrillation - physiopathology; Beta blockers; Biomarkers - blood; Cardiac arrhythmia; Cardiology; Causes of; Chi-Square Distribution; Complications and side effects; Echocardiography, Doppler; Electrocardiography; Electrocardiography, Ambulatory; Exercise tests; Exercise Tolerance; Female; Health Status; Heart failure; Heart Failure - diagnosis; Heart Failure - etiology; Heart Failure - mortality; Heart Failure - physiopathology; Heart Rate; Holter electrocardiography; Humans; Hypertension; Hypertension - complications; Hypertension - diagnosis; Hypertension - mortality; Hypertension - physiopathology; hypertensive heart failure; Logistic Models; Male; Medical prognosis; Methods; Middle Aged; Mortality; Nigeria; Original Research; Predictive Value of Tests; Prognosis; Proportional Hazards Models; Prospective Studies; Reproducibility of Results; Risk Factors; Tachycardia, Ventricular - diagnosis; Tachycardia, Ventricular - etiology; Tachycardia, Ventricular - mortality; Tachycardia, Ventricular - physiopathology; Teaching hospitals; Time Factors; Up-Regulation; Urea - blood; Ventricular Premature Complexes - diagnosis; Ventricular Premature Complexes - etiology; Ventricular Premature Complexes - mortality; Ventricular Premature Complexes - physiopathology; ventricular tachycardia; Walk Test
• ISSN: 1178-2048; 1176-6344; 1178-2048
• DOI: 10.2147/VHRM.S124477

Hypertensive heart failure (HHF) is associated with a poor prognosis. There is paucity of data in Nigeria on prognosis among HHF patients elucidating the role of 24-hour Holter electrocardiogram (ECG) in concert with other risk factors. The aim of this study was to determine the prognostic utility of 24-hour Holter ECG, the 6-minute walk test (6-MWT), echocardiography, clinical and laboratory parameters among HHF patients. A total of 113 HHF patients were recruited and followed up for 6 months. Thirteen of these patients were lost to follow-up, and as a result only 100 HHF patients were analyzed. All the patients underwent baseline laboratory tests, echocardiography, 24-hour Holter ECG and the 6-MWT. HHF patients were analyzed as "mortality vs alive" and as "events vs no-events" based on the outcome at the end of 6 months. Events was defined as HHF patients who were rehospitalized for heart failure (HF), had prolonged hospital stay or died. No-events group was defined as HHF patients who did not meet the criteria for the events group. HHF patients in the mortality group (n = 7) had significantly higher serum urea (5.71 ± 2.07 mmol/L vs 3.93 ± 1.45 mmol/L, = 0.003) than that in those alive. After logistic regression, high serum urea conferred increased mortality risk ( = 0.035). Significant premature ventricular complexes (PVCs) on 24-hour Holter ECG following logistic regression were also significantly higher ( = 0.015) in the mortality group than in the "alive" group (n = 93) at the end of the 6-month follow-up period. The 6-minute walk distance (6-MWD) was least among the HHF patients who died (167.26 m ± 85.24 m). However, following logistic regression, the 6-MWT was not significant ( = 0.777) for predicting adverse outcomes among HHF patients. Patients in the events group (n = 41) had significantly higher New York Heart Association (NYHA) class ( = 0.001), Holter-detected ventricular tachycardia (VT; = 0.009), Holter-detected atrial fibrillation (AF; = 0.028) and PVCs ( = 0.017) following logistic regression than those in the no-events group (n = 59). High NYHA class, elevated serum urea, Holter ECG-detected AF and ventricular arrhythmias are predictive of a poor outcome among HHF patients. The 6-MWT was not a useful prognostic index in this study.