The relationship between serum NT-proBNP levels and severity of coronary artery disease assessed by SYNTAX score in patients with acute myocardial infarction

Background/aim

In the present study, we aimed to investigate the relationship between NT-proBNP and SYNTAX score, which is a measure of the complexity of coronary artery disease.

Materials and methods

We enrolled 405 consecutive patients with myocardial infarction who underwent coronary angiographic examination. Patients were divided into 3 groups according to their SYNTAX scores. Those with SYNTAX score ≤22 were included in the low SYNTAX score group (LSTX), those with a score of 23–32 were included in the intermediate SYNTAX score group (ISTX), and those with a score of ≥33 were included in the high SYNTAX score group (HSTX).

Results

NT-proBNP levels were found to be significantly higher in the HSTX group compared to the other groups (P < 0.001) and in the ISTX group compared to the LSTX group (P < 0.001). The NT-proBNP levels demonstrated an increase from low SYNTAX score to high SYNTAX score tertiles.

Conclusions

NT-ProBNP levels in patients with myocardial infarction on admission were independently associated with extent, severity, and complexity of coronary atherosclerosis as assessed by SYNTAX score.

High-Sensitivity Troponin T and Incident Heart Failure in Older Men: British Regional Heart Study

OBJECTIVE

The aim of this work was to study the association of high-sensitivity troponin T (hsTnT) with incident heart failure (HF), and implications for its use in prediction models.

METHODS AND RESULTS

In the British Regional Heart Study, 3852 men aged 60-79years without baseline HF (3165 without baseline chronic heart disease) were followed for a median of 12.6years, during which 295 incident cases of HF occurred (7.7%). A 1-SD increase in log-transformed hsTnT was associated with a higher risk of incident HF after adjusting for classic risk factors (hazard ratio [HR] 1.58, 95% confidence interval [CI] 1.42-1.77) and after additional adjustment for N-terminal pro-B-type natriuretic peptide (NT-proBNP; HR 1.34, 95% CI 1.19-1.52). The strength of the association between hsTnT and incident HF did not differ by strata of other risk factors. An hsTnT concentration of <5ng/L had a sensitivity of 99.7% (95% CI 98.1%-99.9%) and a specificity of 3.4% (95% CI 2.8%-4.0%). A risk-prediction model including classic risk factors and NT-proBNP yielded a C-index of 0.791, but addition of hsTnT did not further improve prediction (P = .28).

CONCLUSIONS

Elevated hsTnT is consistently associated with risk of HF in older men. HF occurred rarely over 12years when baseline hsTnT was below the limit of detection. hsTnT measurement, however, does not improve HF prediction in a model already containing NT-proBNP.

BNP was associated with ischemic myocardial scintigraphy and death in patients at chest pain unit

BACKGROUND

Recent studies have suggested that B-type Natriuretic Peptide (BNP) is an important predictor of ischemia and death in patients with suspected acute coronary syndrome. Increased levels of BNP are seen after episodes of myocardial ischemia and may be related to future adverse events.

OBJECTIVES

To determine the prognostic value of BNP for major cardiac events and to evaluate its association with ischemic myocardial perfusion scintigraphy (MPS).

METHODS

This study included retrospectively 125 patients admitted to the chest pain unit between 2002 and 2006, who had their BNP levels measured on admission and underwent CPM for risk stratification. BNP values were compared with the results of the MPS. The chi-square test was used for qualitative variables and the Student t test, for quantitative variables. Survival curves were adjusted using the Kaplan-Meier method and analyzed by using Cox regression. The significance level was 5%.

RESULTS

The mean age was 63.9 ± 13.8 years, and the male sex represented 51.2% of the sample. Ischemia was found in 44% of the MPS. The mean BNP level was higher in patients with ischemia compared to patients with non-ischemic MPS (188.3 ± 208.7 versus 131.8 ± 88.6; p = 0.003). A BNP level greater than 80 pg/mL was the strongest predictor of ischemia on MPS (sensitivity = 60%, specificity = 70%, accuracy = 66%, PPV = 61%, NPV = 70%), and could predict medium-term mortality (RR = 7.29, 95% CI: 0.90-58.6; p = 0.045) independently of the presence of ischemia.

CONCLUSIONS

BNP levels are associated with ischemic MPS findings and adverse prognosis in patients presenting with acute chest pain to the emergency room, thus, providing important prognostic information for an unfavorable clinical outcome.

B-type natriuretic peptide and clinical judgment in the detection of exercise-induced myocardial ischemia

BACKGROUND

Myocardial ischemia has been shown to be associated with increased levels of B-type natriuretic peptide (BNP). However, it remains unclear whether and how BNP levels could be used clinically in patients with suspected exercise-induced myocardial ischemia.

METHODS

We enrolled 274 consecutive patients with suspected exercise-induced myocardial ischemia referred for evaluation by rest/bicycle myocardial perfusion single-photon emission computed tomography (SPECT). All clinical information available to the treating cardiologist was used to quantify the clinical judgment regarding the presence of myocardial ischemia using a visual analogue scale twice: once before and once after bicycle exercise stress testing. BNP measurements were obtained before, immediately after, and 2 hours after stress testing in a blinded manner. The presence of myocardial ischemia was adjudicated on the basis of perfusion SPECT combined with coronary angiography findings.

RESULTS

Exercise-induced myocardial ischemia was adjudicated to be present in 103 patients (38%). BNP levels were significantly higher at all time points in patients with myocardial ischemia compared with those without (P < .01 for all). The accuracy of BNP levels as quantified by the area under the receiver operating characteristic curve (AUC) was similar among the time points evaluated (AUC, 0.677-0.697). Combining clinical judgment before exercise testing with BNP levels at rest increased diagnostic accuracy from AUC 0.708 to 0.754 (P = .018). When combining clinical judgment after exercise testing with BNP levels, AUC increased from 0.741 to 0.771 (P = .055).

CONCLUSIONS

Combining clinical judgment with BNP levels increased the diagnostic accuracy regarding the presence of myocardial ischemia.