Description:
Executive Summary
University of Virginia researchers have developed a novel treatment that dramatically improves heart function after a heart attack by modifying the mechanical characteristics of the affected region (the infarct).
Background
Once the myocardium dies during a heart attack, it is gradually replaced over the course of several weeks by scar tissue, accompanied by loss of pumping effectiveness, dilation of the left ventricle and eventual heart failure. Current therapies aim to limit damage during the first few hours by reopening coronary arteries and then slow remodeling and progression to reduce the likelihood of failure over the long term. While the mechanical properties of healing myocardial infarcts are a critical determinant of both depression of pump function and the transition to heart failure, no currently approved drug or device is based on the idea of directly improving heart function by altering infarct mechanical properties.
Invention Description
Infarct properties affect both systolic and diastolic function. A compliant infarct bulges during systole, reducing pump function; a stiffer infarct limits diastolic filling, which also reduces pump function. This novel treatment modifies the mechanical properties of the infarct region in a way that improves systolic function without restricting diastolic filling. In large animal trials, treatment of hearts with large anterior infarcts reversed the increased end-diastolic pressure and acute dilation associated with acute infarction (A) and rescued 50 percent of the deficit in cardiac output (B), allowing hearts to maintain pump function without sympathetic activation or dilation.
Advantages
Unlike available alternatives, this novel treatment:
- Directly improves heart function
- Selectively modifies infarct mechanics to improve systolic function without impeding diastolic filling
- Allows the infarcted heart to maintain cardiac output without the normal physiologic responses of acute dilation or sympathetic activation that increase the likelihood of future remodeling and heart failure
