Left ventricular stroke work reserve as prognostic marker in severe heart failure.

AIM: We sought to determine whether an invasive approach based on Swan-Ganz catheterization, coupled with a pharmacologic stressor, might help stratify prognosis in patients with severe heart failure and uniformly depressed indices of cardiac function. METHODS: We studied 31 unselected consecutive patients with scalar doses of dobutamine (2.5-10 microg/kg/min) after baseline hemodynamic evaluation. Changes in stroke work index (SWI) from baseline to peak effect (stroke work reserve, SWR) were recorded, and patients classified as responders (SWR above the median) or non-responders to dobutamine (SWR below the median). One-year follow-up data were recorded. RESULTS: All patients completed the dobutamine challenge test without complications. Dobuta-mine increased SWI from 17+/-9 to 26+/-13 mg/ beat/m2 (P<0.0001 vs baseline), with a median increase of 6.4 g/beat/m2. Basal SWI was not related to stroke work reserve. The only predictor of response to dobutamine was a smaller left ventricular end-diastolic volume (135+/-28 vs 205+/-90 mL/m2; P=0.007). After 1 year, only 7 patients were alive, while 10 had successful transplantation. Transplant-free survival was 47% in responders vs 0% in non responders (P=0.007). At multivariate analysis, none of baseline hemodynamic parameters was predictive of survival. Only age and a SWR above the median were significant independent predictors of survival in this model. CONCLUSIONS: This study allows us to draw the following conclusions: 1) 1-year mortality in severe heart failure remains extremely high; 2) baseline hemodynamics dos not predict survival; 3) a positive response to dobutamine identifies a subgroup with significant lower mortality at 1 year; 4) this response is an independent predictor of survival and is more likely to occur in the presence of a less dilated left ventricle.

Abciximab in rescue coronary angioplasty after full-dose tissue-type plasminogen activator.

BACKGROUND: Rescue angioplasty is a complex procedure because of frequent reocclusions secondary to a paradoxical pro-thrombotic effect brought about by thrombolytic therapy. Administration of abciximab may improve procedural results but its utilization in this setting is limited by the potential hemorrhagic risk. Very few data on this approach are currently available in the medical literature. METHODS: After failed full-dose tissue-type plasminogen activator (tPA), 30 patients (23 males, 7 females, mean age 64 +/- 13 years) referred for rescue angioplasty received abciximab (0.25 mg/kg bolus + 0.125 mcg/kg/min x 12 hour infusion) (Abc+ group). The procedural results, hemorrhagic complications and in-hospital outcome observed in these patients were compared to those of 35 patients submitted to rescue angioplasty in the same time period (1997-1999) who did not receive abciximab (Abc- group). RESULTS: In the Abc+ group, 11 patients (37%) were in Killip class 3-4, 14 (47%) had multivessel disease, and 4 (13%) had previous bypass surgery. In all Abc+ patients, factors suggestive of procedural failure were present (i.e. saphenous vein graft occlusion, intraluminal thrombus, dissection, reocclusion, slow flow). The periprocedural heparin dose was 5,000 IU in Abc+ and 100 IU/kg in Abc-patients (range 5,000-10,000 IU). The procedure was successful in 29 Abc+ (97%) and in 34 Abc- patients (97%). A hemoglobin drop > 5 g occurred in 3 Abc+ (10%) and in 4 Abc- patients (11%) with a similar incidence of blood transfusion in the two groups. In all these cases, significant bleeding occurred at the vascular access site. There were 2 in-hospital deaths in Abc+ and 1 in Abc- patients. CONCLUSIONS. Selected patients undergoing rescue angioplasty may be treated with abciximab without an undue increase in hemorrhagic complications. Larger studies are needed to confirm the feasibility of this approach and to assess its potential benefits.

Reduced right ventricular ejection fraction as a marker for idiopathic dilated cardiomyopathy compared with ischemic left ventricular dysfunction.

BACKGROUND: Evidence for the role of right ventricular (RV) function is emerging in patients with heart failure of different etiologies. Studies conducted in dilated cardiomyopathy (IDC) showed a high prevalence of RV dysfunction unrelated to the severity of pulmonary hypertension. The aim of the study was to investigate the role of RV dysfunction in ischemic versus nonischemic patients. METHODS: A series of 153 patients with left ventricular (LV) dysfunction (defined as a LV ejection fraction <45%) of either ischemic (n = 61, coronary artery disease [CAD] group) or nonischemic (n = 92, IDC group) origin were studied invasively. Besides routine catheterization data, RV volumes and ejection fractions were obtained angiographically. Reference data were collected in a control group of healthy subjects. RV dysfunction was defined as a RV ejection fraction <35% and ventricular concordance as a <10% difference between RV and LV ejection fraction. The LV/RV end-diastolic volume ratio was calculated to assess the relative dilatation of the ventricular chambers. Hemodynamic and angiographic data were compared in the 2 groups by univariate and multivariate logistic regression analysis. RESULTS: Patients with IDC and CAD had comparable LV ejection fractions (29% +/- 3% vs 31% +/- 8%, P not significant) and mean pulmonary pressures (27 +/- 12 mm Hg vs 26 +/- 11 mm Hg, P not significant); the LV/RV end-diastolic volume ratio was identical in the 2 groups (1.26 +/- 0.4 vs 1.24 +/- 0.4, P not significant). RV ejection fraction was significantly lower in IDC compared with CAD (33% +/- 10 % vs 46% +/- 11%, P <.0001), with a prevalence of RV dysfunction in the IDC group of 65% compared with 16% in the CAD group (P <.0001); similarly, the prevalence of ejection fraction concordance was 74% versus 33%, respectively (P <.0001). At multivariate analysis, a low RV ejection fraction was a powerful independent predictor of IDC compared with CAD (odds ratio 0.91, 95% confidence interval 0.87-0.94, P <.0001). RV dysfunction had a positive predictive value of 75% and a negative predictive value of 78% for the diagnosis of IDC; for ventricular concordance, these values were 81% and 69%, respectively. The correlation between mean pulmonary artery pressure and RV ejection fraction was weaker in the IDC group compared with the CAD group (R(2) = 0.032, P =.047 and R(2) = 0.172,P <.0001, respectively). CONCLUSION: In the presence of LV dysfunction, a reduced RV ejection fraction is a powerful marker for IDC compared with CAD, independent of age, pulmonary hypertension, LV function, and ventricular dimensions. These findings support the concept that IDC is frequently characterized by a biventricular involvement and that the presence of RV dysfunction represents a distinguishing feature of this disease.

Increased cardiac troponin I on admission predicts in-hospital mortality in acute pulmonary embolism.

BACKGROUND: To investigate the frequency of cardiac troponin I (cTnI) increases in patients with pulmonary embolism (PE) and to assess the correlation between this finding, the clinical presentation, and outcomes. METHODS: Consecutive patients admitted to the coronary care unit with acute PE were prospectively enrolled between January 2000 and December 2001. cTnI was sequentially determined. Various cut off concentrations were analysed, but patients were categorised prospectively as having increased or no increased cTnI based on a cut off concentration of 0.6 ng/ml. The main outcome measure was in-hospital mortality. RESULTS: On admission, 14 of the 48 patients (29%) had cTnI concentrations greater than the receiver operating characteristic curve value used to diagnose acute myocardial infarction (> 0.6 ng/ml). Subsequently, six patients developed increases for an overall prevalence of 42% (20 of 42). The prevalence was higher when lower cut off concentrations were used: 73% (35 of 48) at the 99th centile and 60% (29 of 48) at the 10% coefficient of variability. Increased cTnI > 0.6 ng/ml was associated with a slower oxygen saturation (86 (7)% v 93 (4)%, p < 0.0001) and more frequent involvement of the main pulmonary arteries as assessed by spiral computed tomography (100% v 60%, p = 0.022). In-hospital mortality was 36% (5 of 14) of patients with increases > 0.6 ng/ml v 3% (1 of 42) of patients with lower concentrations (p = 0.008). Increased cTnI > 0.6 ng/ml on admission was the most powerful predictor of mortality (p = 0.046). CONCLUSIONS: In high risk patients with acute PE, cTnI was frequently detected on admission. It was the strongest independent predictor of mortality.