ABSTRACT
AIM: To determine the significance of papillary muscle (PM) dysfunction of the mitral valve (MV) and adjacent left ventricular (LV) segments in the genesis of ischemic mitral regurgitation (MR) by myocardial tissue Doppler (MTD) in patients with coronary heart disease (CHD) after surgical treatment. SUBJECTS AND METHODS: One hundred and one CHD patients with moderate (grade I-II) MR were examined before surgical treatment. For analysis, the patients were divided into 4 groups: 1A) 40 patients without progressive, none or moderate MR after isolated aortocoronary bypass surgery (ACBS); 1B) 17 patients with progressive MR to its clinically relevant degree after isolated ACBS; 2A) 30 patients without progressive, none, or moderate MR after ACBS and surgical repair of postinfarction LV aneurysm; 2B) 14 patents with progressive MR to its clinically relevant degree after ACBS and surgical LV repair. The mean follow-up after surgery was 5.35±0.58 years. RESULTS: MTD analysis of the PM function of the MV and adjacent LV segments in the patients with CHD after surgical treatment indicated that those with progressive MR had 1) a decrease in the contractility of both PMs and adjacent LV segments; 2) a restrictive pattern of segmental diastolic dysfunction caused by the high myocardial rigidity of both PMs and adjacent LV segments; 3) an inverse correlation of the posterior PM systolic velocity S with the severity of MR, which is suggestive of the clinically important contribution of posterior PM contractility to the development of MR. There were correlations indicating that the high LV and PM rigidities leading to the restrictive pattern of myocardial diastolic impairments are involved in the development of MR in the patients with CHD. CONCLUSION: The results confirm that PM and adjacent LV segment dysfunctions are of significance in the mechanisms of progressive ischemic MR in the patients with CHD after surgical treatment.
ABSTRACT
AIM: To identify risk and prognostic factors for mitral regurgitation (MR) progression after aortocoronary bypass surgery (ACBS) alone and in combination with surgical left ventricular (LV) reconstruction. SUBJECTS AND METHODS: Data on 101 patients with coronary heart disease who had undergone surgical treatment: ACBS alone in 57 (56%) patients and that in combination with surgical LV reconstruction in 44 (44%). RESULTS: In the late periods after ACBS alone, there was reduced or no MR in 18% of the patients; no substantial changes in MR in 52%, the latter being moderate; progression to significant mitral insufficiency (MI) in 30%. In the same periods after ACBS in combination with surgical LV reconstruction, there was a reduction in MR to its minimum or complete absence in 14% of the patients; no substantial change in the degree of MR in 54%, and progression to significant MI in 32%. The prognostic factors of MI progression after ACBs alone and in combination with surgical LV reconstruction were a more than 32-mm fibrous ring of the mitral valve (MV) (chi2 = 11.62; p = 0.0001); a LV sphericity index of more than 0.65 cm (chi2 = 3.38; p = 0.06); a myocardial scar lesion extent of more than 30% of the LV segments (chi2 = 4.7; p = 0.03); a myocardial reserve of less than 25% (chi2 = 3.1; p = 0.07) (when taking low-dose dobutamine). CONCLUSION: Myocardial revascularization should be combined with MV intervention in patients with moderate MR and risk factors for its progression, such as significant LV remodeling (LV sphericity index of more than 0.65 cm), extensive LV scar lesion (more than 30% of the segments), a low myocardial reserve (less than 25%) during dobutamine test, and a MV fibrous ring of more than 32 mm).
Subject(s)
Coronary Artery Bypass/methods , Coronary Disease/surgery , Heart Ventricles/surgery , Mitral Valve Insufficiency/etiology , Plastic Surgery Procedures/methods , Coronary Angiography , Coronary Disease/complications , Coronary Disease/physiopathology , Disease Progression , Echocardiography , Female , Follow-Up Studies , Humans , Male , Middle Aged , Mitral Valve Insufficiency/diagnosis , Mitral Valve Insufficiency/physiopathology , Prognosis , Severity of Illness Index , Ventricular Function, LeftABSTRACT
Dobutamine Doppler echocardiography was carried out in 56 patients (n=56) with ischemic heart disease and depressed left ventricular function (left ventricular ejection fraction <40%) and chronic heart failure. Clinical signs of heart failure were moderate (NYHA class I-II) in 34 and severe (NYHA class III-IV) in 22 patients. Patients with moderate and severe clinical heart failure had similar degree of left ventricular myocardium impairment however those with severe symptoms had more pronounced right ventricular (RV) dysfunction (greater suppression of global and local RV contractility, greater percentage of irreversibly dysfunctional RV myocardium, lower RV contractile response to dobutamine infusion, more pronounced disturbances of RV diastolic filling). Dependence of RV pump function on pulmonary artery pressure was more evident in patients with severe clinical heart failure and marked dysfunction of RV myocardium than in patients with moderate symptoms and moderate RV myocardial dysfunction.
Subject(s)
Heart Failure/physiopathology , Myocardial Ischemia/physiopathology , Ventricular Dysfunction, Left/physiopathology , Ventricular Dysfunction, Right/physiopathology , Blood Pressure/physiology , Diastole , Echocardiography, Doppler , Echocardiography, Stress , Heart Failure/diagnostic imaging , Humans , Male , Middle Aged , Myocardial Contraction , Myocardial Ischemia/diagnostic imaging , Pulmonary Artery/physiopathology , Ventricular Dysfunction, Left/diagnostic imaging , Ventricular Dysfunction, Right/diagnostic imagingABSTRACT
Segmental right ventricular function was assessed by dobutamine stress echocardiography in 101 patients with ischemic heart disease and multiple coronary artery lesions. At rest local wall motion abnormalities were found in 69% of patients. Overall 505 segments of the right ventricle were analyzed (5 per patient). At baseline 34% of segments were asynergic (31% - hypokinetic and 3% akinetic), right ventricular wall motion score index was 1.38+/-0.04. Low dose dobutamine infusion resulted in decrease of portion of asynergic segments (to 6%) and lowering of wall motion score index (to 1.09+/-0.02, p<0.001 vs baseline). The use of stress doses of dobutamine was associated with appearance of ischemic changes of the right ventricle accompanied with typical anginal attacks and ST-segment depressions; increases of portions of asynergic segments (up to 53% including 43% hypokinetic and 10% akinetic), and of patients with abnormalities of local contractility (up to 90%); rise of wall motion score index (up to 1.64+/-0.05, p<0.001 vs low dose dobutamine). Segmental right ventricular wall motion abnormalities reflected mostly reversible myocardial dysfunction (hibernating myocardium was revealed in 28, scar - in 6, and zone at risk of ischemia - in 47% of all segments). Right ventricular myocardial dysfunction developed in patients with predominant involvement of the right coronary artery or anterior interventricular branch.
