Evaluating the Effects of Nitroglycerin on Heart Function and Urinary Output in Patients With Acute Heart Failure

Impact of Nitroglycerin-induced Vasodilation on Stroke Volume and Diuretic Response in Acute Heart Failure: A Protocol for a Mechanistic Trial

This study aims to understand how nitroglycerin affects patients with acute heart failure, a condition where the heart struggles to pump blood effectively, leading to fluid buildup and breathing difficulties. Nitroglycerin relaxes blood vessels to ease the heart's workload and may help reduce fluid buildup. The investigators hypothesize that nitroglycerin can increase blood flow from the heart and promote urine production, which may reduce congestion in AHF patients. By studying heart function, blood volume, and fluid levels during treatment, the goal is to identify which patients may benefit most from nitroglycerin therapy.

Inclusion Criteria:

• Age ≥ 18 years

• Clinical diagnosis of AHF requiring hospitalization

• Systolic blood pressure ≥85 mmHg

• Echocardiographic signs of cardiac dysfunction, by at least one of

  • Left ventricular ejection fraction ≤45%
  • Abnormal left ventricular filling with dilatation of the left atrium
  • Elevated filling pressures (systolic pulmonary artery pressure>30, dilated vena cava inferior or E/é>10)
  • Significant left-sided heart valve disease

Exclusion Criteria:

• Ongoing ventricular taky- or brady-arrythmias or supraventricular arrhythmias with heart rate > 180 or < 40 bpm.
• Retinopathy or intraocular lens implantation (contraindication to Valsalva maneuver)
• Recent myocardial infarction or thromboembolic events.
• Intake of sildenafil or vardenafil withing 24 h and tadalafil within 48 h.
• Absolute contraindication for vasodilation using nitroglycerin as assessed by treating physician
• Intravenous administration of furosemide within 2 hours of baseline measurements