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[Contraction disorders of the left ventricle in ischemic heart disease. Studies using atrial stimulation]
Insights
Atrial stimulation (AST) effectively diagnoses ischemic heart disease (IHD) by monitoring heart pressures. Elevated mean pulmonary artery pressure (MPAP) during AST is a key indicator for IHD and ventricular aneurysms.
Area of Science:
- Cardiology
- Diagnostic Medicine
- Physiology
Context:
- Ischemic heart disease (IHD) diagnosis requires sensitive and specific methods.
- Atrial stimulation (AST) is an invasive electrophysiological test.
- Assessing cardiac function under stress is crucial for IHD evaluation.
Purpose:
- To evaluate the efficacy of atrial stimulation (AST) in diagnosing ischemic heart disease (IHD).
- To identify hemodynamic parameters indicative of IHD and ventricular dysfunction during AST.
- To correlate hemodynamic changes with coronary artery stenosis and ventricular aneurysms.
Summary:
- Sixty-one patients with suspected IHD underwent AST. Patients with coronary artery disease and ventricular aneurysms (Group C) showed significantly lower maximal and minimal first derivative of left ventricular pressure (dp/dt max/min) and higher left ventricular end-diastolic pressure (LVEDP) and/or mean pulmonary artery pressure (MPAP) compared to controls (Group A) and those with only coronary stenosis (Group B).
- Group B patients exhibited only increased MPAP during AST compared to Group A.
- Reduced contractility was observed in Group C even at rest. AST at heart rates ≥140/min is effective for IHD diagnosis, with abnormal MPAP increase being the simplest indicator. Elevated resting MPAP suggests ventricular aneurysm. A hyperbolic relationship between dp/dt max and LVEDP quantifies contractility.
Impact:
- AST, particularly monitoring MPAP, provides a reliable diagnostic tool for IHD.
- Elevated resting MPAP can serve as an early sign of ventricular aneurysm.
- The study establishes a method for quantitative assessment of cardiac contractility using dp/dt max and LVEDP.
Abstract:
Sixty-one patients with suspected ischemic heart disease (IHD) have been investigated by atrial stimulation (AST). Group A patients had normal coronarograms and served as controls. Group B patients had pathological conronarograms (at least 50% stenosis in one of the 3 vessels) and normal ventriculograms. Group C patients had pathological coronarograms and ventricular aneurysms. During AST, group C patients exhibited lower dp/dt max and dp/dt min as well as higher left ventricular end-diastolic pressure (LVEDP) and/or mean pulmonary artery pressure (MPAP) than groups A and B. Group B differed from group A only by increased MPAP during AST. When compared to controls, contractility in group C was reduced even at rest. AST offers an excellent means of diagnosing IHD if heart rates of 140/min and above are used. An abnormal increase in MPAP serves as the simplest parameter for IHD. Elevated MPAP at rest prompts suspicion of ventricular aneurysm. It is possible to deduce a quanitative estimate of contracitility by correlating dp/dt max to LVEDP. A hyperbolic relation results.