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Ivan Málek

Publications and source records attributed to Ivan Málek.

4 recordsLinked to original sources
PubMed2006

Decrease in plasma B-type natriuretic peptide early after initiation of cardiac resynchronization therapy predicts clinical improvement at 12 months.

BACKGROUND: Decrease in neurohormonal activation during pharmacotherapy for chronic heart failure (CHF) is associated with haemodynamic and clinical improvement. We tested the hypothesis that changes in neurohormonal activation after initiation of cardiac resynchronization therapy (CRT) predict its long-term clinical effect. METHODS: The study group included 43 patients with CHF (37 males, mean age 62+/-9 years, NYHA class 3.2+/-0.4, QRS duration 195+/-24 ms) who underwent successful implantation of a CRT system. Pharmacotherapy remained stable during the first 3 months of follow-up. Plasma levels of B-type natriuretic peptide (BNP) and big endothelin-1 (big ET-1) were evaluated before and 3 months after implantation. Clinical, echocardiographic and exercise parameters were monitored for a mean period of 25.8+/-6.7 months. RESULTS: At 12 months of follow-up 13 non-responders were identified (no improvement in NYHA class (n=10), urgent heart transplantation (n=2) and death due to progressive heart failure (n=1)). CRT resulted in a significant reduction in neurohormone levels (BNP 345.4+/-346 vs. 267.7+/-320.8 pg/ml, p<0.01, big ET-1 3.11+/-1.50 vs. 2.50+/-1.56 fmol/ml p<0.05), especially in responders. Percentage change in BNP level was a stronger predictor of long-term clinical improvement than clinical, echocardiographic and exercise parameters at 3 months of follow-up. CONCLUSIONS: Percentage change in plasma BNP levels from baseline to 3 months was the strongest predictor of long-term response to CRT and may have potential to predict outcome.

Adult↗
PubMed2005

The value of B-type natriuretic peptide and big endothelin-1 for detection of severe pulmonary hypertension in heart transplant candidates.

BACKGROUND: Severe pulmonary hypertension (PH) and increased pulmonary vascular resistance (PVR) are important risk factors that predict early postoperative mortality after orthotopic heart transplantation. The aim of our study was to determine the value of B-type natriuretic peptide (BNP) and big endothelin-1 (big ET1) for prediction of severe PH in heart transplant candidates. METHODS: The study population included 43 potential heart transplant candidates (38 males, mean age 52 +/- 7 years). All underwent repeated right-heart catheterizations (2-5 studies) at an interval of 3-4 months, giving a total of 124 examinations, associated with blood sampling for BNP and big ET1 analysis. Severe PH was defined as the mean pulmonary artery pressure (MPAP) > 40 mmHg. RESULTS: Significantly high PVR (PVR > 3.0 Wood units and TPG > 15 mmHg) was noted on 12 occasions in 10 patients; always in the presence of severe PH. Low BNP levels (<67 pg/ml) ruled out the presence of severe PH with a 100% sensitivity, however, with a low specificity (34%). An increase in plasma BNP > 30 pg/ml (>40% of initial value) in subjects with a previous MPAP< or =40 mmHg detected development of severe PH with a 100% sensitivity and an 80-88% specificity. As a total of 58% of patients presented repeatedly with MPAP< or =40 mmHg, serial BNP testing could reduce the need for hemodynamic studies in this subgroup down to 12-20%. CONCLUSIONS: Serial BNP testing in hemodynamically stable heart transplant candidates with MPAP< or =40 mmHg allows reliable detection of development of severe PH, and may significantly reduce the need for repeated right-heart catheterizations in these patients.

Adult↗
PubMed2003

The effect of cyclosporin A on the level of big endothelin in patients one year after orthotopic heart transplantation.

Orthotopic heart transplantation (OHTx) is currently an established method for the treatment of end-stage heart failure. Persistent elevated plasma endothelin-1 (ET-1) levels have been reported after successful OHTx, the etiology of which is not yet fully understood. Immunosuppressive therapy is assumed to be one of the possible factors affecting ET-1 levels in the body. The present study evaluated the effect of cyclosporin A (CyA) on big ET-1 levels (a precursor of ET-1) in patients 1 year after successful OHTx. The study population comprised 34 patients after OHTx (28 males, 6 females, mean age 49.56+/-11.83 years) divided into two groups according to immunosuppressive protocol (17 patients on cyclosporine-azathioprine-prednisone and 17 patients on cyclosporine-mycophenolate mofetil-prednisone therapy). Plasma levels of big ET-1 and CyA were available for all patients. The control groups consisted of 10 healthy individuals (8 males, 2 females, mean age 41.1+/-11.55 years) and 20 patients with severe heart failure (15 males, 5 females, mean age 54.45+/-8.49 years), respectively. Big ET-1 plasma levels were found to be elevated in OHTx patients in comparison with healthy controls (13.63+/-11.3 fmol/ml vs 2.99+/-1.98 fmol/ml, P=0.005). Big ET-1 plasma levels correlated with plasma CyA levels in patients treated with cyclosporine-azathioprine-prednisone ( r=0.53, P=0.03). This was not the case in either in the OHTx patients as a whole or in the subgroup of patients on cyclosporine-mycophenolate mofetil-prednisone therapy. The plasma levels of big ET-1 are dependent on CyA plasma levels 1 year after successful OHTx in patients treated with the immunosuppressive combination of cyclosporine, azathioprine, and prednisone. As this finding was not observed in the mycophenolate group of patients, mycophenolate mofetil might affect the alteration of the endothelin metabolism.

Cyclosporine↗