Adenosine provokes diastolic dysfunction in microvascular angina

Area of Science:

• Cardiology
• Cardiovascular Physiology
• Diagnostic Imaging

Background:

• Microvascular angina is characterized by chest pain despite normal coronary arteries.
• Assessing cardiac function during stress is crucial for diagnosing and managing angina.
• Diastolic dysfunction can be an early indicator of cardiac compromise.

Purpose of the Study:

• To investigate the effects of adenosine stress on global and regional ventricular function in patients with microvascular angina.
• To determine if adenosine stress induces diastolic dysfunction.
• To evaluate the utility of tissue Doppler echocardiography in detecting stress-induced diastolic dysfunction.

Main Methods:

• Adenosine stress echocardiography was performed in nine patients with microvascular angina.
• Global ventricular function was assessed using Tc(99m) blood pool imaging and Doppler.
• Longitudinal ventricular function was assessed using simultaneous tissue Doppler echocardiography of the lateral mitral annulus.

Main Results:

• Adenosine infusion did not significantly alter global or longitudinal systolic function.
• Adenosine induced global diastolic dysfunction, evident on blood pool imaging and transmitral flow Doppler.
• All patients exhibited long axis diastolic dysfunction at peak adenosine, indicated by a specific mitral annular velocity ratio.

Conclusions:

• Adenosine stress provokes regional and global diastolic dysfunction in microvascular angina.
• Subendocardial ischemia may underlie the observed diastolic dysfunction.
• Tissue Doppler of the lateral annular motion is a sensitive method for detecting long axis diastolic dysfunction.