Left ventricular versus biventricular dysfunction in idiopathic dilated cardiomyopathy.

Eighty-five consecutive patients with idiopathic dilated cardiomyopathy were categorized according to the presence (biventricular dysfunction) or absence (left ventricular [LV] dysfunction) of reduced right ventricular ejection fraction (<35%) along with reduced LV ejection fraction (<50%). Compared with the 36 patients with LV dysfunction, the 49 patients with biventricular dysfunction had significantly worse New York Heart Association functional class (2.7+/-0.6 vs 1.9+/-0.5; p <0.001), LV ejection fraction (26+/-10% vs 34+/-8%; p <0.0001), and outcome (transplant-free survival, 55% vs 89%; p <0.001). Thus, dilated cardiomyopathy is frequently characterized by biventricular involvement, which identifies a more severe disease and a worse long-term prognosis.

Cardiac troponin I as diagnostic and prognostic marker in severe heart failure.

BACKGROUND: Cardiac cell death has been shown to occur in heart failure and has been implicated as one of the mechanisms responsible for progression of the disease. Cardiac Troponin I (cTnI) represents a highly sensitive marker for myocardial cell death. Based on previous studies reporting that cTnI may be detected in patients with heart failure, we evaluated the clinical correlates and prognostic implications of detectable cTnI in a consecutive series of patients with severe heart failure. METHODS: Thirty-four patients were examined. Upon admission, we measured serum levels of cTnI by conventional immunoenzymatic assay (Stratus Dade II). According to the results of this assay, patients were divided into 2 groups, based on the presence (cTnI+) or absence (cTnI-) of detectable cTnI. These 2 groups were compared by non-parametric analysis for their clinical characteristics, instrumental findings, and short-term outcome. RESULTS: The cTnI+ group included 10 patients (29%) with a mean serum cTnI of 0.7 +/- 0.3 ng/ml. Compared with the cTnI- group, these patients had significantly lower left ventricular ejection fractions (20% +/- 5% vs 26% +/- 7%, p = 0.023) and a trend for higher systolic pulmonary artery pressure (59 +/- 17 mm Hg vs 49 +/- 13 mm Hg, p = 0.08). In cTnI+ patients, the correlation between cTnI levels upon admission and ejection fraction was r = -0.530 (p = 0.11). We found ischemic etiology was equally present in the 2 groups, whereas we never found histologic signs of acute myocarditis. Other clinical characteristics (functional class, daily diuretic dose, need for intravenous inotropes) were not statistically different in the 2 groups. In cTnI+ patients who improved after admission, cTnI became undetectable after a few days; in patients with refractory heart failure who were hospitalized until death, cTnI persisted in detectable levels throughout the observation period. Using the Cox proportional hazard model, a positive cTnI was the most powerful predictor of mortality at 3 months (p = 0.013; hazard ratio 6.86; 95% confidence interval 1.32 to 35.4). CONCLUSIONS: These observations suggest that cTnI is detected in the blood of 25% to 33% of patients with severe heart failure; its presence may help to identify a high-risk sub-group who faces very poor short-term prognosis.

Subacute thrombosis after stenting in acute myocardial infarction: four-year experience in a low-volume center.

BACKGROUND: Despite substantial technical and therapeutic improvements, subacute stent thrombosis (SST) remains a feared complication of stenting, especially in acute coronary syndromes. Results of large interventional trials obtained in selected highly skilled centers may underestimate the incidence of SST in the real world of interventional cardiology. OBJECTIVE: To analyze the incidence of SST after stenting in acute myocardial infarction (AMI) and to identify clinical or procedural parameters associated with its occurrence in a center performing < 40 interventional procedures in AMI per year. MATERIALS AND METHODS: The authors examined their catheterization laboratory database and analyzed a series of 80 consecutive patients treated with stenting for AMI from 1995 to 1998. The incidence of SST among these patients (AMI group) was compared with that observed among 389 elective patients treated during the same period (non-AMI group). Then, results obtained for AMI patients treated during the first half of the study period (1995-1996) were compared with those obtained for patients treated during 1997-1998. RESULTS: The incidence of SST in AMI group was 6.3%, significantly higher (P < 0.0001) than the 0.5% which occurred in non-AMI group. However, all cases of SST were concentrated during the first half of the experience, whereas no case was reported among the 47 patients treated during 1997-1998 (P = 0.016). Although most clinical and angiographic baseline data for the two study periods were comparable, less bail-out stenting (17 versus 42%; P = 0.024) and higher maximal inflation pressure (15 +/- 4 versus 13 +/- 5; P = 0.031) were found during the latter period. CONCLUSION: The authors conclude that SST after stenting in AMI was significantly decreased. Relatively low-volume centers should not be denied the possibility of performing interventional procedures in the clinical setting of AMI, provided that results and complication rates are within pre-defined standards of adequacy.

Hemodynamic correlates of atrial natriuretic peptide concentration in unselected patients with heart disease of different etiologies.

BACKGROUND: Although a large number of studies have investigated the relationship between atrial natriuretic peptide (ANP) concentrations and circulatory abnormalities, it is presently unsettled as to whether this parameter provides valuable information in unselected patients with heart disease of different etiologies regardless of the presence of left ventricular dysfunction or heart failure. AIM OF THE STUDY: The aim was to evaluate the correlation between ANP, hemodynamics and parameters of ventricular function in a large series of consecutive patients and to define the predictive value of ANP for the identification of specific circulatory abnormalities. METHODS: Cardiac catheterization was performed in 167 consecutive patients (62% males; mean age 62 yrs; range 18-85) and ANP serum levels were determined concomitantly by single antibody immune assay. Underlying etiology was: ischemic (67), valvular (72), idiopathic (12) and miscellaneous (16). Data management included: comparison of patients according to ANP values > or < 50% percentile of the cumulative distribution curve (i.e. 140 pg/ml); analysis of ANP concentrations according to the presence of normal or abnormal ventricular filling pressures; correlation between hemodynamic parameters and ANP concentrations; correlation of ANP with ventricular function in the whole population and in subgroups; calculation of sensitivity and specificity of ANP for the identification of abnormal filling pressures. RESULTS: Mean ANP concentration was 181 +/- 139 pg/ml. Patients with ANP < 140 had significantly lower right-sided pressures but similar ventricular volumes and ejection fractions. By multivariate analysis, the single independent predictor of ANP was wedge pressure (p < 0.0001). Regarding etiology, severe mitral regurgitation was associated with the highest ANP levels (259 +/- 122 pg/ml), although the difference was not significant. The presence of abnormal left and right ventricular filling pressures was associated with significantly higher levels of ANP (p < 0.0001). A level of 125 pg/ml proved to be fairly sensitive (79%) but poorly specific (66%) for the detection of an abnormal wedge pressure. ANP was related to ventricular function only in the small subgroup of patients with dilated cardiomyopathy, where a significant negative correlation was found with both left ventricular (r = -0.72; p = 0.008) and right ventricular ejection fraction (-0.71; p = 0.01). CONCLUSIONS: In unselected cardiac patients, ANP is confirmed to be a marker of left ventricular filling pressure in spite of poor specificity. Ventricular function appears to be related to ANP concentrations only in the subgroup of patients with pure heart-muscle disease.

LV systolic performance improves with development of hypertrophy after transverse aortic constriction in mice.

Transverse aortic constriction (TAC) is an effective technique for inducing left ventricular (LV) hypertrophy in mice. With the use of transthoracic echocardiography and Doppler measurements, we studied the effects of an acute increase in pressure overload on LV contractile performance and peak systolic wall stress index (WSI) at early time points after TAC and the time course of the development of LV hypertrophy in mice. The LV mass index was similar between TAC and sham-operated mice at postoperative day 1 but progressively increased in TAC mice by day 10. There was no further increase in the LV mass index between postoperative days 10 and 20. On day 1, whereas peak systolic WSI increased significantly, the LV ejection fraction (LVEF) and percent fractional shortening (%FS) decreased in TAC mice compared with sham-operated mice. By day 10, peak systolic WSI, LVEF, and %FS had recovered to baseline levels and were not significantly different between postoperative days 10 and 20. Thus LV systolic performance in mice declines immediately after TAC, associated with increased peak systolic WSI, but recovers to baseline levels with the development of compensatory LV hypertrophy over 10-20 days.

Assessment of right ventricular function and interstitial fibrosis in idiopathic dilated cardiomyopathy: hemodynamic correlates and prognostic value.

BACKGROUND: Right ventricular (RV) function and morphometric quantitation of interstitial fibrosis in idiopathic dilated cardiomyopathy (IDC) have not been the subject of specifically designed clinical observations. In particular, their role in routine assessment and prognostic evaluation of patients (pts) with IDC remains to be settled. METHODS: Eighty-one consecutive IDC patients (63 M, 18 F; mean age 52 +/- 11 yrs) with left ventricular (LV) systolic dysfunction (angiographic ejection fraction - EF - < 55%), normal coronary arteries and no histologic evidence of myocarditis were studied. Cardiac catheterization and endomyocardial biopsy (EMB) were routinely performed in all cases. RV volumes and EF were obtained by angiography according to Ferlinz' method and interstitial fibrosis was quantitated by computer-assisted morphometric analysis. These data were analyzed in order to study correlations with hemodynamic parameters and to assess their prognostic value in a long-term follow-up. RESULTS: In the study population, right ventricular EF was significantly lower than in normal controls (35 +/- 11% vs 53 +/- 6%, p < 0.0001) and showed a significant positive correlation with LV EF (r = 0.54; p < 0.0001), and a weak but significant negative correlation with fibrosis (r = -0.29; p = 0.03). RV volumes, but not EF, were significantly related to mean pulmonary pressure. At multivariate analysis, RV end-diastolic volume (EDV) and EF were the two independent predictors of severe heart failure (NYHA class III-IV). After a mean follow-up of 64 +/- 36 months, 20 pts died and 9 had heart transplantation, for a 63% transplant-free survival rate (TFS). Multivariate analysis identified three independent predictors of TFS: LV stroke work index (p < 0.0001), RV stroke work index (p = 0.02) and RV EDV (p = 0.03). Fibrosis was predictive of survival only in the subgroup with LV EF < 20%. CONCLUSIONS: Assessment of RV function provides useful information in the evaluation of hemodynamic profile and prognosis of pts with IDC. Quantitation of interstitial fibrosis by morphometry provides little additional data.