Independent Predictors Of Clinical Events Research Articles

Effect of interaction between left ventricular dysfunction and endothelial function in hypertension

Hypertension, one of the most important risk factors for cardiovascular diseases, is associated with both left ventricular hypertrophy and endothelial dysfunction. Both have been recently recognized as independent predictors of clinical events in different groups of patients. In fact, a dysfunctioning endothelium loses its antiatherosclerotic and antithrombotic action, and, therefore, promotes the atherosclerotic process. Similarly, cardiac hypertrophy is recognized as a powerful and independent risk factor for cardiovascular morbidity and mortality because it predisposes to arrhythmias and maximizes the consequences of acute myocardial ischemia. Recently, an evident interaction has been demonstrated between endothelial dysfunction and left ventricular mass. In particular, the coexistence of both left ventricular hypertrophy and endothelial dysfunction almost doubles the risk for future vascular events in hypertensives. Thus, in hypertensive patients, it is clinically useful to choose an aggressive therapeutic strategy--to reduce left ventricular mass and to improve endothelial function.

Serum hepatocyte growth factor levels predict long-term clinical outcome after percutaneous coronary revascularization

To evaluate, in patients referred for elective percutaneous coronary revascularization (PCR) without heparin pre-treatment, the relationship between baseline serum levels of the angiogenic growth factors, vascular endothelial growth factor (VEGF) and hepatocyte growth factor (HGF), and clinical outcome. In 488 consecutive patients undergoing elective coronary angioplasty, hsC-reactive protein, HGF, and VEGF levels were measured before heparin administration. The primary endpoint, a composite of death and myocardial infarction, occurred in 44 patients at a median follow-up of 14.9 months. At baseline, VEGF levels were related to C-reactive protein levels and inversely related to age; HGF levels were related to C-reactive protein levels, diabetes, and recent clinical instability. In the univariate analysis, HGF had a significant positive relationship (P=0.003) with the primary endpoint. A similar trend was observed for VEGF (P=0.11). The only three variables significantly associated with the primary endpoint in the multivariable Cox model were HGF (P=0.004), C-reactive protein (P=0.007), and diabetes (P=0.04). Our results demonstrate that in patients, without heparin pre-treatment, referred for PCR, a high serum level of HGF is an independent predictor of clinical events during follow-up and is correlated with other surrogate measures of the activity of atherosclerosis.

Prognostic value of endocardial electromechanical mapping in patients with left ventricular dysfunction undergoing percutaneous coronary intervention

Endocardial electromechanical mapping (EEM) has been proposed as a method for myocardial viability assessment. However, the impact of EEM data on clinical outcome has not been studied before. We sought to assess the prognostic value of EEM in patients with left ventricular (LV) dysfunction undergoing percutaneous coronary intervention (PCI). Seventy-five patients with coronary artery disease and LV dysfunction (angiographic LV ejection fraction [EF] 49 +/- 15%) underwent LV EEM for myocardial viability assessment before coronary revascularization. EEM parameters included mean unipolar electrographic amplitude, mean local shortening, LV volumes, LVEF, number of regions with electrographic amplitudes <7.5 mV, number of electromechanical mismatch, and match regions. Cardiac death, nonfatal myocardial infarction, nonfatal stroke, and acute heart failure requiring hospitalization were defined as clinical events. During a follow-up of 3.6 +/- 1.8 years, 20 clinical events occurred. Event-free survival after coronary revascularization was significantly better in patients with a mean unipolar electrographic amplitude of >/=9.5 mV than in patients with a mean unipolar electrographic amplitude of <9.5 mV (88% vs 57%; p <0.005). Cox regression analysis revealed angiographic LVEF, mean electrographic amplitude, number of regions with electrographic amplitudes <7.5 mV, number of electromechanical match regions, and EEM EF as univariate predictors of clinical events. In a multivariate analysis, angiographic LVEF <40% (hazard ratio 4.78, p <0.005) and mean electrographic amplitude <9.5 mV (hazard ratio 2.92, p <0.05) were independent predictors of clinical events. Thus, EEM provides prognostic information in patients with LV dysfunction undergoing coronary revascularization.

Peak exercise oxygen pulse and prognosis in chronic heart failure

Cardiopulmonary variables, particularly peak oxygen consumption (peak VO 2) corrected for total and lean body weight, have been confirmed to predict prognosis in patients with chronic systolic heart failure (HF). Only limited data are available on the prognostic ability of maximal oxygen (O 2) pulse, an indicator of stroke volume and arteriovenous O 2 difference, especially when corrected for lean body mass. Cardiopulmonary exercise tests were performed in 209 consecutive patients with mild-to-moderate HF (mean ejection fraction 23%), followed for 19 ± 12 months to determine the impact of maximal O 2 pulse in relation to other cardiopulmonary variables on major clinical events (13 cardiovascular deaths and 15 urgent transplantations). Compared with patients with clinical events, those without major events had a higher peak O 2 pulse (11.4 ± 4.1 vs 9.2 ± 2.3 ml/beat, p <0.0001) and body fat-adjusted peak O 2 pulse (15.6 ± 5.6 vs 11.9 ± 3.4 ml/beat, p <0.0001). In multivariate analysis, a low peak O 2 pulse was the strongest independent predictor of clinical events (chi-square 10.5, p <0.01). Although peak O 2 pulse was a stronger predictor for clinical events than any other exercise cardiopulmonary variable, including peak VO 2, peak VO 2 lean (defined as the VO 2 corrected for lean body mass), and percentage of predicted peak VO 2, this relation was further strengthened by correcting peak O 2 pulse for percent body fat (chi-square 12.4, p <0.001). In most subgroups (including women, obese subjects, those receiving β blockers, and those with class III HF), peak O 2 pulse lean was similar to or superior to peak VO 2 lean for predicting major clinical events. Especially in patients who were class III HF and who were receiving β blockers, peak VO 2 (cutoff 14 ml/kg/min) poorly predicted prognosis; risk stratification was best with peak O 2 pulse lean (cutoff 14 ml/beat). These data indicate the potential usefulness of peak O 2 pulse and lean body mass–adjusted O 2 pulse for predicting prognosis in patients with systolic HF.

Serial measure of cardiac troponin T levels for prediction of clinical events in decompensated heart failure

Background This study determined whether serial determinations of cardiac troponin T (cTnT) in decompensated heart failure (HF) are predictive of clinical events (death, need for readmission for new episode of HF decompensation, or both) during 1 year of follow-up. Methods and results Sixty-two patients with decompensated HF were enrolled in this cohort. The first measurement of cTnT (cTnT1) was from a blood sample drawn within 4 days of hospital admission; the second measurement (cTnT2) was on blood obtained 7 days later. Forty-nine clinical events (16 deaths, 10 readmissions, 23 combined readmission and deaths) occurred during the follow-up. The independent predictors of clinical events were: cTnT1 > .020 ng/mL ( P<.050), cTnT2 > .020 ng/mL ( P<.050), and serum sodium<135 mEq/L ( P<.050). Based on levels of cTnT1 and cTnT2 > .020 ng/mL (+) or ≤0.020 ng/mL(–), patients were divided into 2 groups: group 1 (cTnT1−, cTnT2− or cTnT1+, cTnT2−), group 2 (cTnT1−, cTnT2+ or cTnT1+, cTnT2+). Group 2 patients had higher rates of death (45.0% versus 71.4%, P<.050), hospital readmission (35.0% versus 61.9%, P<.050), and clinical events (55.0% versus 90.5%, P<.010) than group 1 patients. Conclusions Persistently increased cTnT levels (>.020 ng/mL) are predictive of higher rates of death and hospital readmission for decompensated HF.

Comparison of event and procedure rates following percutaneous transluminal coronary angioplasty in patients with and without previous coronary artery bypass graft surgery (the ROSETTA Registry)

To compare 6-month post-percutaneous transluminal coronary angioplasty (PTCA) outcomes and cardiac procedure use among patients with and without prior coronary artery bypass graft (CABG) surgery, we examined 791 patients who were enrolled in the Routine versus Selective Exercise Treadmill Testing after Angioplasty (ROSETTA) Registry. The ROSETTA Registry is a prospective, multicenter registry that examines the use of functional testing after successful PTCA. Most patients were men (76%, mean age 61 ± 11 years) who underwent single-vessel PTCA (85%) with stent implantation (58%). Baseline and procedural characteristics differed between patients with a prior CABG (n = 131) and patients with no prior CABG (n = 660), including Canadian Cardiovascular Society angina class III to IV (60% vs 49%, respectively, p = 0.03) and stenosis involving the proximal left anterior descending coronary artery (10% vs 22%, p = 0.004). Event rates among patients with prior CABG were higher than among patients with no prior CABG, including unstable angina (19% vs 11%, p = 0.02), myocardial infarction (2% vs 1%, p = 0.2), death (4% vs 2%, p = 0.08), and composite clinical events (22% vs 12%, p = 0.003). Furthermore, patients with prior CABG had higher rates of follow-up cardiac procedures, including angiography (24% vs 14%, p = 0.008) and PTCA (13% vs 7%, p = 0.04), but not repeat CABG (2% vs 3%, p = 0.8). A multivariate analysis that included baseline clinical and procedural characteristics demonstrated that prior CABG was a significant independent predictor of clinical events and cardiac procedure use (odds ratio 2.3, 95% confidence interval 1.5 to 3.5, p = 0.0001). Within the prior CABG group, patients with a PTCA of a bypass graft had a higher composite clinical event rate than patients with a PTCA of a native vessel (32% vs 17%, p = 0.05). In contrast, patients with a PTCA of a native vessel had event rates similar to those of patients with no prior CABG (17% vs 12%, p = 0.2). Thus, post-CABG patients have an increased risk of developing a cardiac event or needing a follow-up cardiac procedure during the 6 months after PTCA.

Pulsatile hemodynamics in hypertension.

The hemodynamics of hypertension and antihypertensive therapy have generally been approached in terms of the steady-flow load on the heart. Recent evidence, however, suggests that the pulsatile component of hemodynamic load may play a fundamental role in both the development and progression of hypertensive cardiovascular disease and its clinical sequelae. Pulse pressure, a correlate of conduit vessel stiffness, has been shown to be an important independent predictor of clinical events in hypertensive patients and in the general population. Unrecognized effects on pulsatile hemodynamics may account for the differential effects of various agents on left ventricular mass and events. A better understanding of abnormalities in pulsatile load in hypertension will facilitate risk stratification in and treatment of patients with hypertension.