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Combining loop with thiazide diuretics for decompensated heart failure: the CLOROTIC trial
Joan Carles Trullàs1,2, José Luis Morales-Rull3, Jesús Casado4
1Internal Medicine Department, Hospital dOlot i comarcal de la Garrotxa, Girona, Av dels Pasos Catalans, 86, 17800 CA, Spain.
Insights
Adding hydrochlorothiazide (HCTZ) to intravenous furosemide improved weight loss and diuresis in acute heart failure patients. However, it increased the risk of impaired renal function without affecting dyspnea or mortality.
Area of Science:
- Cardiology
- Nephrology
- Pharmacology
Background:
- Acute heart failure (AHF) is a complex condition often requiring aggressive diuresis.
- Loop diuretics like furosemide are standard treatment, but diuretic resistance can occur.
- Optimizing diuretic strategies is crucial for managing fluid overload in AHF.
Purpose of the Study:
- To determine if adding hydrochlorothiazide (HCTZ) to intravenous furosemide enhances diuretic response in AHF patients.
- To assess the safety and efficacy of this combination therapy.
Main Methods:
- A prospective, double-blind, placebo-controlled trial involving 230 AHF patients.
- Patients received intravenous furosemide plus either HCTZ or a placebo.
- Coprimary endpoints included changes in body weight and dyspnea at 72 hours; secondary outcomes assessed diuresis, renal function, electrolytes, and mortality.
Main Results:
- Patients receiving HCTZ showed significantly greater weight loss (2.3 kg vs. 1.5 kg) and 24-hour diuresis (1775 mL vs. 1400 mL) compared to placebo.
- No significant difference was observed in patient-reported dyspnea.
- HCTZ use was associated with a higher incidence of impaired renal function (46.5% vs. 17.2%), but electrolyte disturbances and mortality rates were similar between groups.
Conclusions:
- The addition of hydrochlorothiazide to loop diuretics improves diuretic response in patients with acute heart failure.
- While effective for fluid management, this combination requires careful monitoring for renal function changes.
Aims:
To evaluate whether the addition of hydrochlorothiazide (HCTZ) to intravenous furosemide is a safe and effective strategy for improving diuretic response in acute heart failure (AHF).
Methods And Results:
A prospective, double-blind, placebo-controlled trial, including patients with AHF randomized to receive HCTZ or placebo in addition to an intravenous furosemide regimen. The coprimary endpoints were changes in body weight and patient-reported dyspnoea 72 h after randomization. Secondary outcomes included metrics of diuretic response and mortality/rehospitalizations at 30 and 90 days. Safety outcomes (changes in renal function and/or electrolytes) were also assessed. Two hundred and thirty patients (48 women, 83 years) were randomized. Patients assigned to HCTZ were more likely to lose weight at 72 h than those assigned to placebo [2.3 vs. 1.5 kg; adjusted estimated difference (notionally 95 confidence interval) 1.14 (1.84 to 0.42); P 0.002], but there were no significant differences in patient-reported dyspnoea (area under the curve for visual analogue scale: 960 vs. 720; P 0.497). These results were similar 96 h after randomization. Patients allocated to HCTZ showed greater 24 h diuresis (1775 vs. 1400 mL; P 0.05) and weight loss for each 40 mg of furosemide (at 72 and at 96 h) (P 0.001). Patients assigned to HCTZ more frequently presented impaired renal function (increase in creatinine 26.5 moL/L or decrease in eGFR 50; 46.5 vs. 17.2; P 0.001), but hypokalaemia and hypokalaemia were similar between groups. There were no differences in mortality or rehospitalizations.
Conclusion:
The addition of HCTZ to loop diuretic therapy improved diuretic response in patients with AHF.
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