The haemodynamic effects of subcutaneous sumatriptan, a 5HT₁‐receptor agonist

Abstract

Aims Previous in vivo studies with sumatriptan, a 5HT 1 -receptor agonist, have demonstrated vasopressor responses in the pulmonary and systemic arterial circulation. Pulmonary artery wedge pressure (PAWP) also increases after sumatriptan injection, raising the possibility of an additional venoconstrictive action or a negative inotropic effect. The mechanism for the rise in PAWP was investigated in the study. Methods Ten patients undergoing diagnostic coronary arteriography underwent haemodynamic monitoring. Results There was a significant rise (P<0.05) in systemic and pulmonary arterial pressure and total systemic and pulmonary vascular resistance. There was a similar rise (P<0.05) in PAWP and left ventricular end diastolic pressure (LVEDP). There was no change in cardiac output nor in peak rate of left ventricular pressure rise (dP/dt). Conclusions The sumatriptan induced rise in PAWP and LVEDP appears consequent upon increased afterload although a negative inotropic effect cannot be excluded.Keywords: sumatriptan, 5-hydroxytryptamine, vasoconstriction, haemodynamics Each patient was issued an appropriate information sheet Introduction and written informed consent was obtained. Sumatriptan, is a selective 5HT 1 -receptor agonist effective in the acute treatment of migraine [1, 2] . Previous in vivoHaemodynamic monitoring studies with sumatriptan have demonstrated vasopressorAfter the diagnostic procedure, a pigtail catheter was responses in the systemic and pulmonary circulation with an employed to measure systemic arterial and left ventricular additional rise in pulmonary artery wedge pressure (PAWP) pressure. A left ventricular pressure tracing was expanded to [3, 4]. The increase in PAWP was postulated to be secondary 100 mm s −1 and digitised to allow the calculation of peak to pulmonary venoconstriction but direct measurement of rate of rise of pressure (dP/dt). Right atrial, pulmonary the left atrium or left ventricular end diastolic pressure was artery and pulmonary artery wedge pressures were measured not made to exclude a rise in PAWP due to a reduction in with a Swan Ganz catheter. Cardiac output was measured left ventricular contractile function. In order to investigate by the thermodilution technique. Hard copy ECGs and this further, we assessed the effects of a standard dose of pressure tracings were recorded at 10 min intervals, following sumatriptan (6 mg s.c.) on standard haemodynamic paramplacebo and sumatriptan (6 mg) subcutaneous injection. As eters including simultaneous measurement of the PAWP and drug administration was single-blinded, pressure tracings and LVEDP and on inotropic effects by measuring the peak rate ECGs were analysed by a blinded observer. of left ventricular pressure rise (dP/dt). Results MethodsAs shown in Table 1 and Figure 1, there were significant Ten patients (3M57F-aged 49±9 years) were studied changes (P<0.05 ANOVA) in systemic (SVR) and pulmonfollowing the conclusion of diagnostic coronary arterioary vascular resistance (PVR), right atrial pressure (RAP, graphy. A...

Allergic lung inflammation induces pulmonary vascular hyperresponsiveness

“…In control lungs, 5-HT evoked only a moderate vascular pressor response, which is in line with previous studies [21]. Acute vasoconstriction to 5-HT was mediated by the 5-HT1B receptor in human pulmonary arteries ex vivo [37] and in vivo [38], whereas in normal rat pulmonary arteries, these responses were mediated predominantly by the 5-HT2A receptor [39]. In ex vivo perfused lungs of allergen-sensitised and -challenged mice, as well as control mice, the 5-HT-evoked Ppa responses were blocked by the 5-HT2A receptor antagonist ketanserin, whereas 5-HT1B receptor antagonism by GR127935 did not diminish vasoconstriction.…”

Acute effects of sumatriptan on aortic blood pressure, stiffness, and pressure waveform

“…19,30 An increase in aortic blood pressure has been observed previously in patients undergoing diagnostic coronary angiography, by use of invasive blood pressure monitoring. 4,5,7,31,32 However, in these studies no comparisons were made with simultaneously measured brachial blood pressure. A novel finding of our study is that the central increase in SBP was more pronounced than the peripheral increase in SBP.…”

Atrial fibrillation following oral sumatriptan administration

“…Hood et al demonstrated significant increase in left ventricular end diastolic and pulmonary artery wedge pressures following subcutaneous sumatriptan [8]. Altered atrial filling resulting from these haemodynamic changes could be responsible for initiating AF [9].…”