lusitropy
Pronunciation: loo-SIT-ro-pee
The property of myocardial relaxation; positive lusitropy enhances diastolic relaxation while negative lusitropy impairs it.
Full Definition
The cardiac property that describes the rate and completeness of ventricular relaxation during diastole, which affects ventricular filling and diastolic function. Positive lusitropic agents such as milrinone enhance myocardial relaxation by improving calcium reuptake into the sarcoplasmic reticulum, leading to better diastolic filling at lower pressures. Negative lusitropic effects, seen with ischemia or certain medications, result in impaired relaxation and elevated filling pressures. In cardiac anesthesia, lusitropic function is particularly important in patients with diastolic dysfunction or restrictive cardiomyopathy.
Usage
Usage note: Less commonly used than other -tropic terms; specifically refers to relaxation rather than contraction.
In Context
- "Milrinone's positive lusitropy improved diastolic filling in the patient with restrictive cardiomyopathy." — Pharmacotherapy note
- "Ischemia-induced negative lusitropy contributed to the elevated pulmonary capillary wedge pressure." — Hemodynamic analysis