Seguridad y tolerancia del tratamiento con bloqueadores beta en el paciente anciano con insuficiencia cardíaca. Estudio BETANIC

Gaps in Medical and Device Therapy for Patients with Left Ventricular Systolic Dysfunction: The EchoGap Study

Objectives:

To assess gaps between guidelines and medicine prescription/dosing and referral for defibrillator therapy in patients with left ventricular systolic dysfunction (LVSD).

Methods:

Outpatient echocardiography reports at an academic hospital centre were screened and outpatients with LVEF<40% were included. A questionnaire was mailed to the patients’ physician, querying prescription/dosing of ACE-inhibitors (ACEi), angiotensin receptor blockers (ARB) and beta-blockers (BB). Patients with LVEF<30% had additional questions on implantable cardiac defibrillator (ICD) referral.

Results:

Mean age was 69.6+/-12.2 years and mean LVEF was 29.7+/-6.5%. ACEi and/or ARB prescription rate was 260/309(84.1%) versus 256/308(83.1%) for BB (p=NS for comparison). Of patients on ACEi, 77/183(42.1%) were on target dose, compared to 7/45(15.5%) for ARB and 9/254(3.5%) for BB (p<0.01). Of 171/309 patients (55.3%) with LVEF<30%, 72/171(42.1%) had an ICD and 16/171(9.4%) were referred for one.

Conclusion:

Prescription rates of evidence-based HF medicines are relatively high in outpatients with LVSD referred for echocardiography at this Canadian academic medical centre; however, the proportion of patients at target doses was modest for ACEi and low for ARB and BB. Approximately half of patients who qualify for ICD by EF alone have one or were referred. Important reasons for patients with LVSD not on evidence-based therapy were identified.

Has beta-blocker use increased in patients with heart failure in internal medicine settings? Prognostic implications: RICA registry

INTRODUCTION AND OBJECTIVES

Underuse of beta-blockers has been reported in elderly patients with heart failure. The aim of this study was to evaluate the current prescription of beta-blockers in the internal medicine setting, and its association with morbidity and mortality in heart failure patients.

METHODS

The information analyzed was obtained from a prospective cohort of patients hospitalized for heart failure (RICA registry] database, patients included from March 2008 to September 2011) with at least one year of follow-up. We investigated the percentage of patients prescribed beta-blockers at hospital discharge, and at 3 and 12 months, and the relationship of beta-blocker use with mortality and readmissions for heart failure. Patients with significant valve disease were excluded.

RESULTS

A total of 515 patients were analyzed (53.5% women), with a mean age of 77.1 (8.7) years. Beta-blockers were prescribed in 62.1% of patients at discharge. A similar percentage was found at 3 months (65.6%) and 12 months (67.9%) after discharge. All-cause mortality and the composite of all-cause mortality and readmission for heart failure were significantly lower in patients treated with beta-blockers (hazard ratio=0.59, 95% confidence interval, 0.41-0.84 vs hazard ratio=0.64, 95% confidence interval, 0.49-0.83). This decrease in mortality was maintained after adjusting by age, sex, ejection fraction, functional class, comorbidities, and concomitant treatment.

CONCLUSIONS

The findings of this study indicate that beta-blocker use is increasing in heart failure patients (mainly elderly) treated in the internal medicine setting, and suggest that the use of these drugs is associated with a reduction in clinical events.

Can migraine prophylaxis prevent acute mountain sickness at high altitude?

Acute mountain sickness (AMS) develops in people trekking at high altitude. The underlying mechanism is vasodilation due to low pressure of oxygen. However, individual susceptibility for AMS is unknown, thus, one cannot predict when or to whom it happens. Because AMS usually begins with headache, and because migraineurs are more vulnerable to AMS, we studied by the literatures review on the mechanism and clinical features in common, and assessed the treatment modalities for both disorders. This led to us the following hypothesis that, migraine prophylaxis may prevent or delay the onset of AMS at high altitude. Clinical features of AMS include nausea or vomiting when it progresses. Hypobaric hypoxia, dehydration or increased physical exertion trigger or aggravate both disorders. In migraine, cerebral vasodilation can happen following alteration of neuronal activity, whereas the AMS is associated with peripheral vessel dilation. Medications that dilate the vessels worsen both conditions. Acute treatment strategies for migraine overlap with to those of AMS, including drugs such as vasoconstrictors, or other analgesics. To prevent AMS, adaptation to high altitude or pharmacological prophylaxis, i.e., acetazolamide has been recommended. This carbonic anhydrase inhibitor lowers serum potassium level, and thus stabilizes membrane excitability. Acetazolamide is also effective on specific forms of migraine. Taken together, these evidences implicate that migraine prophylaxis may prevent or delay the onset of AMS by elevating the threshold for high altitude.