[Medical expert consensus in AH on the clinical use of triple fixed-dose antihypertensive therapy in Spain]

INTRODUCTION

The opinion of experts (different specialties) on the triple fixed-dose antihypertensive therapy in clinical practice may differ.

MATERIALS AND METHODS

Online questionnaire with controversial aspects of the triple therapy answered by panel of experts in hypertension (HT) using two-round modified Delphi method.

RESULTS

The questionnaire was completed by 158 experts: Internal Medicine (49), Nephrology (26), Cardiology (83). Consensus was reached (agreement) on 27/45 items (60%); 7 items showed differences statistically significant. Consensus was reached regarding: Predictive factors in the need for combination therapy and its efficacy vs. increasing the dose of a pretreatment, and advantage of triple therapy (prescription/adherence/cost/pressure control) vs. free combination.

CONCLUSIONS

This consensus provides an overview of the clinical use of triple therapy in moderate-severe and resistant/difficult to control HT.

[Underestimation of renal risk in cardiology clinics. RICAR study]

AIMS

The aim of this study was to assess the rate of patients attended in cardiology outpatient clinics in whom microalbumine or glomerular filtration rate had been determined, at least once, in the previous 12 months.

METHODS

It was an observational, transversal, multicentric study. 1224 patients were included from 124 centers in Spain. Epidemiological, anthropometric, analytic and electrocardiographic data were recruited. Glomerular filtration rate was calculated thereafter by means of the simplified equation of the MDRD. Results. Microalbumine was determined in 34% of the patients, of those 49% had positive microalbumine. Microalbumine rates were higher in patients with diabetes, heart failure, atrial fibrillation, peripheral artery disease or serum creatinine levels > 1.3 mg/dl. However, only young patients, diabetics and those with left ventricular hypertrophy had this exam performed more often. The glomerular filtration rate was determined in 11% of the patients. 30% of the population had moderate or severe renal dysfunction (filtration rate < 60 ml/min) and only 21% of the population hat normal renal function (filtration rate > 90 ml/min). Glomerular filtration rate was assessed more frequently in patients with serum creatinine > 1.3 mg/dl and those with history of heart failure.

CONCLUSIONS

The prevalence of renal dysfunction in hypertensive patients attended in Cardiology clinics is high. However, the methods recommended for early detection of renal dysfunction are scarcely used by cardiologists. These figures do not improve significantly in high risk patients.

R 56865 delays cellular electrical uncoupling in ischemic rabbit papillary muscle

The compound R56865 protects the heart from irreversible ischemic damage. The proposed mechanism of its action is a reduction of Ca2+ overload secondary to a reduction of intracellular Na+, caused by blockade of the Na(+)-channel. In addition, cardioprotection is ascribed to blockade of the Na(+)-sensitive K(+)-channel (IK-Na). We tested whether R 56865 delays cellular electrical uncoupling, one aspect of irreversible ischemic damage that is due to Ca2+ overload. Also, we studied whether the Na(+)-channel and IK-Na are involved in cardioprotection by relating delay of the onset of cellular electrical uncoupling to changes of conduction velocity and action potential duration (APD80), respectively. Experiments were performed with isolated perfused rabbit papillary muscles that were treated with 1 microM R 56865 for 45 min prior to ischemia. Uncoupling started at 15.0 +/- 0.8 min (mean +/- S.E.M., n = 12) of ischemia in the control group and at 23.4 +/- 1.7 min in the R 56865 group (n = 9, P < 0.005 vs control). R 56865 tended to decrease conduction velocity and to increase APD80 during pre-treatment, but these changes were not statistically significant. During ischemia, conduction velocity was statistically not different between the R 56865 group and the control group. APD80 was significantly longer in the R 56865 than in the control group during the first 7 min of ischemia and similar after that. We conclude that R 56865 delays the onset of cellular uncoupling during ischemia and that this effect is not related to changes of conduction velocity and at most in part to changes of APD80.

Ischaemic preconditioning delays ischaemia induced cellular electrical uncoupling in rabbit myocardium by activation of ATP sensitive potassium channels

OBJECTIVE

The aim was to examine whether ischaemic preconditioning delays the onset of cellular electrical uncoupling during ischaemia, and whether the effect of preconditioning is mediated by the activation of ATP sensitive K+ channels (IK-ATP).

METHODS

Onset of uncoupling, action potential duration (APD80), and conduction velocity were measured in an isolated perfused rabbit papillary muscle. Preconditioning consisted of 10 min occlusion and 10 min reperfusion prior to 40 min sustained ischaemia. Five groups were studied: (1) control (sustained ischaemia only); (2) preconditioning; (3) preconditioning with 20 microM glibenclamide, a blocker of IK-ATP, added for 10 min during the reperfusion period; (4) sustained ischaemia after 15 min perfusion with 20 microM cromakalim (BRL 34915), an opener of IK-ATP; (5) sustained ischaemia after 10 min perfusion with 20 microM glibenclamide without preconditioning.

RESULTS

Uncoupling started at 15.0(SEM 0.7) min of ischaemia in the control group and at 22.8(1.5) min after preconditioning (p < 0.001 v control group). Blocking IK-ATP during the preconditioning protocol with glibenclamide abolished the delay of uncoupling: onset was at 14.7(1.2) min. Activation of IK-ATP with cromakalim resulted in uncoupling at 23.3(1.9) min (p < 0.002 v control). Glibenclamide without preconditioning had no effect on uncoupling: onset was at 15.6(1.0) min. APD80 during ischaemia was significantly shorter in the preconditioning and cromakalim groups than in the control group from 5 min of ischaemia onward. In the preconditioning+glibenclamide group and the glibenclamide group APD80 was at no point significantly different from the control group. Conduction velocity during ischaemia decreased to about 70% of baseline after 10 min and was not different between the five groups.

CONCLUSIONS

(1) Preconditioning delays the onset of electrical uncoupling; (2) the protective effect of preconditioning may be caused by activation of the IK-ATP channel; (3) the protective effect is associated with reduction of action potential duration, but not with changes of conduction velocity.