An elevated level of BNP in plasma is related to the development of good collateral circulation in coronary artery disease

N-terminal pro-brain natriuretic peptide and coronary collateral formation in patients undergoing primary percutaneous coronary intervention

There is insufficient information on the relationship between the N-terminal pro-brain natriuretic peptide (NT-proBNP) level and collateral circulation (CC) formation after primary percutaneous coronary intervention (PCI) in patients with ST-segment elevation myocardial infarction. We analyzed 857 patients who underwent primary PCI. The serum NT-proBNP levels were measured on the day of admission, and the CC was scored according to Rentrop’s classification. Log-transformed NT-proBNP levels were significantly higher in patients with good CC compared to those with poor CC (6.13 ± 2.01 pg/mL versus 5.48 ± 1.97 pg/mL, p < 0.001). The optimum cutoff value of log NT-proBNP for predicting CC was 6.04 pg/mL. Log NT-proBNP ≥ 6.04 pg/mL (odds ratio 2.23; 95% confidence interval 1.51–3.30; p < 0.001) was an independent predictor of good CC. CC development was higher in patients with a pre-TIMI flow of 0 or 1 than those with a pre-TIMI flow of 2 or 3 (22.6% versus 8.8%, p = 0.001). The incidence of left ventricular (LV) dysfunction (< 50%) was greater in patients with a pre-TIMI flow of 0 or 1 (49.8% versus 35.5%, p < 0.001). The release of NT-proBNP was greater in patients with LV dysfunction (34.3% versus 15.6%, p < 0.001). The incidence of good CC was greater in patients with log NT-proBNP levels ≥ 6.04 pg/ml (16.8% versus 26.2%, p = 0.003). The association between NT-proBNP and collateral formation was not influenced by pre-TIMI flow and LV function. NT-proBNP appears to reflect the degree of collateral formation in the early phase of STEMI and might have a new role as a useful surrogate biomarker for collateral formation in patients undergoing primary PCI.

Increasing heart vascularisation after myocardial infarction using brain natriuretic peptide stimulation of endothelial and WT1+ epicardial cells

Brain natriuretic peptide (BNP) treatment increases heart function and decreases heart dilation after myocardial infarction (MI). Here, we investigated whether part of the cardioprotective effect of BNP in infarcted hearts related to improved neovascularisation. Infarcted mice were treated with saline or BNP for 10 days. BNP treatment increased vascularisation and the number of endothelial cells in all areas of infarcted hearts. Endothelial cell lineage tracing showed that BNP directly stimulated the proliferation of resident endothelial cells via NPR-A binding and p38 MAP kinase activation. BNP also stimulated the proliferation of WT1⁺ epicardium-derived cells but only in the hypoxic area of infarcted hearts. Our results demonstrated that these immature cells have a natural capacity to differentiate into endothelial cells in infarcted hearts. BNP treatment increased their proliferation but not their differentiation capacity. We identified new roles for BNP that hold potential for new therapeutic strategies to improve recovery and clinical outcome after MI.

Influence of collaterals on the left ventricular end-diastolic pressure and serum NT-proBNP levels in patients with coronary chronic total occlusion

Objective

Although numerous studies have shown the protective effects of the well-developed coronary collaterals on left ventricular functions, the relationship between collateral grade and left ventricular end diastolic pressure has not been studied in chronic total occlusion patients. Also, there are conflicting data on the effect of collaterals on NT-proBNP levels. The aim of our study was to evaluate the relationship between coronary collateral circulation and left ventricular end diastolic pressure and NT-proBNP levels in chronic total occlusion patients.

Methods

Study group was retrospectively selected from the patients who had undergone coronary angiography at our hospital between June 2011 and March 2013. Clinical, biochemical, angiographic and hemodynamic data of 199 consecutive patients having at least one totally occluded major epicardial coronary artery were evaluated. Coronary collateral circulation was graded according to Rentrop classification. While Rentrop grade 3 was defined as well-developed, all the remaining collateral grades were regarded as poor collaterals.

Results

Overall 87 patients were found to have good collaterals and 112 patients had poor collaterals. There was no significant difference between the patients with well- or poorly developed coronary collaterals with regard to left ventricular end diastolic pressure (16.84 ± 5.40 mmHg vs 16.10 ± 6.09, respectively, p = 0,632) and log NT-proBNP (2.46 ± 0.58 vs 2.59 ± 0.76, respectively, p = 0,335).

Conclusion

In patients with coronary chronic total occlusion even well-developed coronary collaterals are not capable of protecting the rise of left ventricular end diastolic pressure and NT-proBNP levels which are reliable markers of the left ventricular dysfunction.

Coronary collateral circulation in patients with chronic coronary total occlusion; its relationship with cardiac risk markers and SYNTAX score

BACKGROUND

Compared to patients without a collateral supply, long-term cardiac mortality is reduced in patients with well-developed coronary collateral circulation (CCC). Cardiovascular risk markers, such as N-terminal pro-brain natriuretic peptide (NT-proBNP), high-sensitive C-reactive protein (hs-CRP) and high-sensitive cardiac troponin T (hs-cTnT) are independent predictors for cardiovascular mortality.

OBJECTIVES

The main goal of this study was to examine the relationship between CCC and cardiovascular risk markers.

METHODS

We prospectively enrolled 427 stable coronary artery disease patients with chronic total occlusion (mean age: 57.5±11.1 years). The patients were divided into two groups, according to their Rentrop scores: (a) poorly developed CCC group (Rentrop 0 and 1) and (b) well-developed CCC group (Rentrop 2 and 3). NT-proBNP, hs-CRP, hs-cTnT, uric acid and other biochemical markers were also measured. The SYNTAX score was calculated for all patients.

RESULTS

The patients in the poorly developed CCC group had higher frequencies of diabetes and hypertension (p<0.05 for both). Compared to the well-developed CCC group, the SYNTAX score, Hs-cTnT, hs-CRP, NT-proBNP, uric acid, neutrophil count and mean platelet volume (MPV) values were higher in patients with poorly developed CCC (p<0.05 for all). On multivariate logistic regression analysis, hs-cTnT (β=0.658, 95% CI=0.589-0.735, p<0.001) and NT-proBNP (β=0.991, 95% CI=0.987-0.995, p<0.001) as well as hs-CRP and diabetes were independent predictors of CCC.

CONCLUSION

Cardiac risk markers, such as NT-proBNP, hs-cTnT and hs-CRP are independently associated with CCC in stable coronary artery disease with chronic total occlusion.