Prognostic relevance of heart rate at rest for survival and the quality of life in patients with dilated cardiomyopathy

Anesthetic Management of Patients with Dilated Cardiomyopathy Undergoing Noncardiac Surgery

Dilated cardiomyopathy (DCM), a primary myocardial disease, is characterized by dilation of the left or both ventricles and systolic dysfunction with or without congestive heart failure. DCM per se is a well-recognized risk factor for sudden cardiac death and poor surgical outcomes following noncardiac surgery. Surgical trauma/stress represents unique challenges for DCM patient management. Unfortunately, there is a big knowledge gap in managing DCM patients undergoing non-cardiac surgery. Therefore, the aim of our review is to provide basic facts and current advances in DCM, as well as a practical guideline to perioperative care providers, for the management of surgical patients with DCM, who are quite rare compared with the general surgical population. This review summarizes recent advances in the medical management of DCM as well as perioperative assessment and management strategies for DCM patients undergoing noncardiac surgery. Optimal surgical outcomes depend on multiple-disciplinary care to minimize perioperative cardiovascular disturbances.

Impact of diabetes mellitus and its complications: survival and quality-of-life in critically ill patients

PURPOSE

Diabetes mellitus represents an increasing problem for patients and health care systems worldwide. We sought to investigate the effect of diabetes and its associated comorbidities on long-term survival and quality of life following an admission to a medical intensive care unit (ICU).

METHODS

A total of 6662 consecutive patients admitted to ICU between 2004 and 2009 were included (patients with diabetes n=796, non-diabetic patients n=5866). The primary endpoint of the study was death of any cause. Data on mortality was collected upon review of medical records or phone interviews. Moreover, a questionnaire was sent to 500 randomly selected patients addressing Health related Quality of Life (HrQoL) after ICU treatment.

RESULTS

Overall mortality did not differ significantly between diabetic and non-diabetic patients after ICU treatment (mean follow-up time: 490 days). For a subgroup of patients already exhibiting comorbidities associated with diabetes, the mortality rate was significantly higher (p=0.022). Regarding quality of life, no differences were found between groups.

CONCLUSIONS

Diabetes was not associated with increased mortality or reduced quality of life in a general population of medical ICU patients. However, once comorbidities associated with diabetes occurred, the survival rate of patients with comorbidities associated with hyperglycemia was significantly reduced.

Novel and nonpharmacologic approaches to cardio-protection in hypertension

Hypertension has wide (30-45 %) prevalence in the general population and is related to important increases in overall cardiovascular morbidity and mortality. Despite lifestyle modifications and optimal medical therapy (three drugs, one being diuretic), about 5-20 % of hypertensives are affected by resistant hypertension. Chronic high blood pressure has adverse effects on the heart and other organs such as the kidneys and vasculature. Renal sympathetic denervation and baroreceptor stimulation are invasive approaches initially investigated to treat resistant hypertension. Their pleiotropic effects appear promising in cardiovascular remodeling, heart failure and arrhythmias and could potentially affect cardiovascular morbidity and mortality.

Capacidade funcional como preditor de qualidade de vida na insuficiência cardíaca

INTRODUÇÃO: A insuficiência cardíaca (IC) prejudica a qualidade de vida (QV), enquanto a reabilitação cardiopulmonar e metabólica (RCPM) de pacientes com a síndrome proporciona melhora da capacidade funcional (CF) e da qualidade de vida. OBJETIVOS: Determinar a relação dos domínios da QV com a CF de pacientes com IC, assim como propor pontos de corte dos domínios da QV por meio da CF. MATERIAIS E MÉTODOS: Avaliou-se 57 pacientes com IC, classe funcional II e III, sendo 37 ingressantes (GI) no programa de RCPM e 20 participantes (GP) com mais de três meses de programa. A QV foi avaliada pelo questionário de Minnesota por meio dos domínios físicos, emocionais e dimensões gerais. A CF foi determinada por meio do teste de caminhada de seis minutos (TC6'), tendo pontos de corte definidos conforme proposto na literatura. Utilizou-se teste t de Student, correlação de Pearson e análise da curva ROC para responder aos objetivos da pesquisa, considerando significância de 5%. RESULTADOS: Participantes da RCPM apresentaram melhores escores da QV quando comparados aos ingressantes. Correlações significativas foram observadas entre o domínio emocional e TC6' para ambos os grupos. Verificou-se pontos de corte significativos dos domínios da QV advindos da CF, com destaque ao domínio emocional (sensibilidade/especificidade) para ambos os grupos. CONCLUSÃO: Os portadores de IC com mais de três meses de RCPM apresentaram melhor QV e capacidade funcional do que os iniciantes. O domínio emocional do questionário de Minnesota se mostrou um bom preditor de ponto de corte da capacidade funcional.

Effects of carvedilol therapy on cardiac autonomic control, QT dispersion, and ventricular arrhythmias in children with dilated cardiomyopathy

BACKGROUND

The purpose of this study was to examine the effects of carvedilol therapy on autonomic control of the heart and QT-interval dispersion (QTd) among children with idiopathic dilated cardiomyopathy (DCM) whose symptoms were not adequately controlled with standard congestive heart failure therapy.

MATERIAL AND METHODS

Patients with DCM who were treated with carvedilol were enrolled in the study. All patients had undergone carvedilol therapy in addition to standard therapy for at least 6 months. Clinical, echocardiographic, and electrocardiographic parameters, and 24-h Holter records of patients were retrospectively evaluated before and after carvedilol treatment.

RESULTS

A total 34 patients (mean age: 7.4 ± 4.3 years) with DCM were analyzed in the study. The median follow-up period was 9.5 months. After the 6 months of carvedilol therapy the clinical score significantly improved, left ventricular ejection fraction (LVEF) and fractional shortening (LVFS) significantly increased, and left ventricle end-diastolic dimensions and end-systolic dimensions significantly decreased. There were statistically significant increases in mean SDNN, SDANN, rMSSD, and pNN50 (p = 0.002, p = 0.001, p = 0.008, and p = 0.026, respectively). After the carvedilol therapy, SDNN was correlated with the clinical score, heart rate, LVEF, LVFS, and total premature ventricular contractions (PVCs). In addition, rMSSD and pNN50 were correlated with heart rate, LVEF and LVFS. A significant reduction was observed in QTc-minimum, QTc-maximum, and QTd values (434.9 ± 40.7 vs. 416.1 ± 36.5, 497.8 ± 43.6 vs. 456.3 ± 41.7, 58.6 ± 17.1 vs. 49.3 ± 15.6; p < 0.001, p = 0.001, and p = 0.008, respectively). QTd was significantly related to PVCs (r = 0.62, p = 0.02).

CONCLUSIONS

We conclude that the addition of carvedilol to standard therapy can improve clinical symptoms and heart rate variability, and reduce in arrhythmia markers in children with DCM.

Ivabradine: potential clinical applications in critically ill patients

It has been extensively demonstrated that an elevated heart rate is a modifiable, independent risk factor for cardiovascular events. A high heart rate increases myocardial oxygen consumption and reduces diastolic perfusion time. It can also increase ventricular diastolic pressures and induce ventricular arrhythmias. Critical care patients are prone to develop a stress induced cardiac impairment and consequently an increase in sympathetic tone. This in turn increases heart rate. In this setting, however, heart rate lowering might be difficult because the effects of inotropic drugs could be hindered by heart rate reducing drugs like beta-blockers. Ivabradine is a new selective antagonist of funny channels. It lowers heart rate, reducing the diastolic depolarization slope. Moreover, ivabradine is not active on sympathetic pathways, thus avoiding any interference with inotropic amines. We reviewed the literature available regarding heart rate control in critical care patients, focusing our interest on the use of ivabradine to assess the potential benefits of the drug in this particular setting.

Long-term prognostic value of elevated heart rate one year after heart transplantation

BACKGROUND

Elevated heart rate (HR) is associated with adverse cardiovascular outcome in the general population and in patients with cardiovascular disease. Elevated HR due to graft denervation is often found in heart transplantation (HTx) patients; the effect on graft survival and vasculopathy is unclear. Thus, the aim of this study was to evaluate the role of elevated HR at 12 months post-HTx and its power to predict HTx long-term outcome.

METHODS

We evaluated retrospectively a prospective database of 312 patients undergoing HTx at two centers. HR was registered at 12 months post-HTx. The median HR was used as a cutoff point. Cox regression analysis was performed with variables known to be clinically relevant to mortality and those selected from the univariate analysis.

RESULTS

During a mean follow-up of 5.5 ± 2.8 years there were 58 deaths (19%). Patients with a HR ≥ 90 bpm (median HR) at 12 months had an increased risk for all-cause mortality (Hazard Ratio=2.4, 95% CI 1.2 to 4.5, p=0.009) and mortality related to coronary allograft vasculopathy (CAV) (Hazard Ratio=3.0, 95% CI 1.25-7.14, p=0.01). Multivariate analysis showed that a HR ≥ 90 bpm independently predicted mortality (HR 3.2, 95% CI 1.4-7.1, p=0.004).

CONCLUSIONS

Elevated HR measured at 12 months after HTx is an independent predictor of all-cause mortality in HTx recipients. A HR ≥ 90 bpm identifies a group of patients at high risk of death and CAV-related mortality at mid- to long-term.