Influence of ATII blockers and calcium channel blockers on renal vascular resistance in patients with essential hypertension

Scientific paper - Original scientific paper

• Title (croatian): Utjecaj ATII blokatora i blokatora kalcijskih kanala na bubrežni krvožilni otpor u bolesnika s esencijalnom hipertenzijom
• Author: Diana Delić-Brkljačić
• Author: Krešimir Galešić
• Author: Gordana Ivanac
• Author: Šime Manola
• Author: Hrvoje Pintarić
• Author: Krešimir Štambuk
• Author: Petar Gaćina
• Author: Vjekoslav Radeljić
• Author's institution: University of Zagreb; School of Medicine
• Scientific / art field, discipline and subdiscipline: BIOMEDICINE AND HEALTHCARE; Clinical Medical Sciences

Abstract (english)

Doppler can evaluate renal vascular resistance, and resistance index (RI) highly correlates with blood pressure and renal function in various pathological conditions. Purpose of the study was to measure and compare renal Doppler indices in patients with newly-diagnosed essential hypertension (EH) and in healthy subjects; to determine changes of Doppler indices in patients after six-months monotherapy with either the AT II blocker (valsartane) or calcium channel blocker (niphedipine); to determine which drug has better renoprotective effect. 65 healthy controls were examined, as well as 69 patients with the newly-diagnosed EH, without signs of the target organ damage. Duplex Doppler US of interlobar intrarenal arteries was performed, and RI, acceleration index (AI) and acceleration time (AT) measured. Antihypertensive monotherapy was performed with vaslartane in 34 patients and with niphedipine in 35 patients. Doppler was repeated after the six-months therapy. RI in patients with the 1. stage of EH is significantly higher compared to the controls (p<0.001), and significantly lower compared to the stage 2. of EH (p<0.001). The significant decrease of systolic (p<0.001) and dyastolic blood pressure (BP) (p<0.001) was noted after the therapy. RI in healthy examinees (RI=0.59±0.023) is significantly lower than in EH (RI=0.66±0.26) (p<0.001), while AI is significantly higher (p<0.001), and AT is significantly lower (p<0.001). In patients treated with valsartane and those treated with niphedipine, the RIs are significantly lower than before (p<0.001), while AIs were significantly higher, and ATs were significantly lower after the therapy after the therapy with both drugs. RIs in patients treated with valsartane (RI = 0.615 ± 0.036) are significantly lower than RIs of patients treated with niphedipine (RI=0.642±0.030) (p<0.01) after therapy. Regression analysis for the predictive values of RI, AT, AI in relation to the age-standardized values of systolic and diastolic BP of healthy examinees and patients with hypertension has demonstrated that RI is the strongest and statistically significant predictor in all groups of examinees. Six-months monotherapy of EH with valsartane or with niphedipine is equally efficient in the decrease of the blood pressure, but valsartane has more favourable effect on kidney. Resistance index measured in intrarenal arteries is the best parameter of Doppler spectrum in the evaluation of the effects of antihypertensive therapy on the kidney.

Abstract (croatian)

Dopler je koristan u procjeni bubrežnog krvožilnog otpora, a indeks otpora (RI) korelira značajno s krvnim tlakom i funkcijom bubrega u brojnim patološkim stanjima. Cilj je izmjeriti i usporediti bubrežne doplerske indekse kod bolesnika s novodijagnosticiranom esencijalnom hipertenzijom (EH) i zdravih osoba; odrediti promjene doplerskih indeksa u bolesnika nakon šestomjesečne monoterapije ili AT II blokatorom (valsartan) ili blokatorom kalcijskih kanala (nifedipin); odrediti koji lijek ima bolji renoprotektivni učinak. Pregledano je 65 zdravih osoba i 69 bolesnika s novodijagnosticiranom EH bez znakova oštećenja ciljnih organa. Dupleks dopler ultrazvukom intrarenalnih interlobarnih arterija izmjereni su RI, akceleracijski indeks (AI) i akceleracijsko vrijeme (AT). Antihipertenzivna monoterapija je provedena valsartanom u 34 bolesnika, a nifedipinom u 35 bolesnika. Dopler je ponovljen nakon provedene šestomjesečne terapije. RI u bolesnika s prvim stadijem EH je značajno viši u usporedbi sa zdravim ispitanicima (p<0,001), a značajno niži u usporedbi s drugim stadijem EH (p<0,001). Značajan pad sistoličkog (p<0,001) i dijastoličkog krvnog tlaka (KT) (p<0,001) je uočen nakon liječenja. RI u zdravih ispitanika (RI=0,59±0,023) je značajno niži nego kod EH (RI=0,66±0,26) (p<0,001), dok je AI značajno viši (p<0,001), a AT značajno niže (p<0,001). U bolesnika liječenih i valsartanom i nifedipinom vrijednosti RI su značajno niže nego prije liječenja (p<0,001), vrijednosti AI su značajno više, a AT značajno niže, i to nakon liječenja s oba lijeka. RI nakon liječenja kod bolesnika liječenih valsartanom (RI=0,615±0,036) je značajno niži od RI kod bolesnika liječenih nifedipinom (RI=0,642±0,030) (p<0,01). Regresijska analiza za prediktivne vrijednosti RI, AT, AI u odnosu na dobno-standardizirani sistolički i dijastolički KT zdravih ispitanika i hipertoničara pokazala je da je RI najjači i statistički značajan prediktor u svim skupinama ispitanika. Šestomjesečna monoterapija EH valsartanom ili nifedipinom je jednako djelotvorna u smanjenju krvnog tlaka, ali valsartan ima bolje djelovanje na bubreg. Indeks otpora u intrarenalnim arterijama je najbolji parametar doplerskog spektra u procjeni djelovanja antihipertenziva na bubreg.

• Keywords (english): Adult; Angiotensin II Type 1 Receptor Blockers/pharmacology; Calcium Channel Blockers/pharmacology; Croatia; Female; Humans; Hypertension/drug therapy; Hypertension, Renovascular/prevention & control; Hypertension, Renovascular/ultrasonography; Kidney/drug effects; Male; Middle Aged; Regression Analysis; Tetrazoles/pharmacology; Ultrasonography, Doppler, Duplex; Valine/analogs & derivatives; Valine/pharmacology; Vascular Resistance
• Language: english
• Publication type: Scientific paper - Original scientific paper
• Publication status: Published
• Peer review: Peer review
• Publication version: Published version
• Journal title: Collegium Antropologicum
• Numbering: vol. 33, no. 4, pp. 1129-1138
• p-ISSN: 0350-6134
• URN:NBN: urn:nbn:hr:105:581674
• Publication: 2009-12
• Document URL: https://hrcak.srce.hr/51474
• Type of resource: Text
• Access conditions: Open access
• Created on: 2024-03-28 11:38:13