• Cerebrovascular Disease
• Prevention & Screening
• Heart Failure

Ronald Freudenberger, MD, Center for Advanced Heart Failure, Allentown, PA, listed some of the similarities between the pathophysiology of heart failure (HF) and stroke.

In addition to having a history of diabetes mellitus and/or hypertension, cardiac patients also have a high rate of silent cerebral infarcts (SCI): approximately 15% of diagnostic and percutaneous coronary intervention patients [Segal AZ et al. Neurology 2001]; 17% of coronary artery bypass graft patients [Friday G et al. Heart Surgery Forum 2005]; and 34% of patients who are referred for transplantation [Siachos T et al. J Card Fail 2005] have been shown to have an SCI.

HF likely is a prothrombotic state. Plasma viscosity, serum P-selectin, von Willebrand factor, and fibrinogen are higher in HF patients [Gibbs CR et al. Circulation 2001], and there also is an increase in whole blood aggregation and platelet/EC adhesion molecules [Serebruany V et al. Eur J Heart Fail 2002].

“Heart failure and stroke are strongly related and often coexist in the same population. Both share common risk factors and characteristics, including activation of inflammatory and thrombotic systems,” said Dr. Freudenberger (Table 1).

Commenting on the cerebral effects of decreased cardiac output, Patrick Pullicino, MD, University of Kent, Canterbury, UK, noted that a relationship has been shown between increases in New York Heart Association (NYHA) Functional Class and reductions in global cerebral blood flow (CBF), with higher functional class being associated with lower CBF [Choi BR et al. Am J Cardiol 2006; Venegas-Torres et al. ISC 2009].

Other evidence for brain injury in HF comes from MRI studies that showed that asymptomatic patients with cardiomyopathy and low EF had a higher incidence of stroke, cortical atrophy, and ventricular enlargement [Schmidt R et al. Stroke 1991].

There also is increasing evidence that relative hypotension may be injurious to the brain in HF. Results from the REGARDS trial showed that the OR for stroke was higher for patients with HF versus those without. The association was strongest in individuals in the lowest blood pressure group, suggesting that cerebral hypoperfusion could contribute to stroke pathogenesis. These results need to be confirmed, although they are supported by a pooled analysis of 10 HF studies that showed that higher systolic BP decreases mortality [Raphael CE et al. Heart 2009].

Ralph L. Sacco, MD, University of Miami, Miami, FL, reviewed several studies that examined stroke outcome in patients with HF, noting that for such patients, in-hospital mortality is nearly 2 times higher, length of stay is greater, and total cost is higher (Table 2) [Divani A et al. J Cardiac Heart Fail 2009].

HF in stroke patients also may be an important predictor of recurrent stroke or death within 2 years after TIA or stroke, according to a study by Kernan et al. [Kernan WN et al. Stroke 2000]. Classical vascular risk factors (such as age, prior stroke, hypertension, and history of/current diabetes mellitus) add to the risk of stroke among those with HF.

Dr. Sacco remarked, “The public health impact of HF may be even greater than AF, particularly when you take into account prevalence and mortality.”

• © 2009 MD Conference Express