October 1, 1986Circulation
Left ventricular remodeling after myocardial infarction: a corollary to infarct expansion.
Population
30 patients with their first acute transmural myocardial infarction who were treated successfully with…
Design
Cohort
Follow-up
2 weeks
Authors
Discussion
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Implication
Post-MI LV dilatation involves global remodeling; supports hypothesis of remote segment involvement but should not yet change practice.
Key Points
- To determine whether left ventricular remodeling after acute myocardial infarction involves noninfarcted segments in addition to the expansion of infarcted zones.
- Assessed 30 patients with a first acute transmural myocardial infarction (15 anterior, 15 inferior) who received successful thrombolytic therapy.
- Conducted serial left ventricular angiography, hemodynamic measurements, and M-mode echocardiography on admission and at 2-week follow-up.
- Measured endocardial perimeter lengths of akinetic-dyskinetic infarction zones and noninfarction zones in patients showing at least a 20% increase in left ventricular end-diastolic volume (LVEDV).
- At 2 weeks, both LVEDV and end-systolic volume indexes significantly increased (p < 0.01), with LVEDV expansion correlating directly with initial akinetic or dyskinetic area (r = 0.71, p < 0.001).
- Patients with ≥20% LVEDV increase demonstrated a mean 13% perimeter increase in infarcted segments and a 19% increase in noninfarcted segments, with no change in noninfarcted wall thickness.
- Left ventricular and pulmonary capillary wedge pressures significantly decreased (p < 0.01), while angiographic cardiac index significantly increased (p < 0.01).
Structured PICO
P
Population
30 patients with their first acute transmural myocardial infarction (15 anterior, 15 inferior) who were treated successfully with thrombolytic therapy and demonstrated improvement of flow in an occluded coronary artery.
O
Outcome
Left ventricular geometric changes assessed by left ventricular angiography and M mode echocardiography at 2 weekssurrogate
In the early convalescent period after myocardial infarction, cardiac dilatation involves remodeling of the entire left ventricle, including both infarct expansion and volume-overload hypertrophy of noninfarcted segments.
Cite This Study
McKay et al. (1986) studied this question.