Patients with hypertrophic cardiomyopathy exhibited a significantly greater maximal change in coronary sinus pH during dipyridamole stress compared to controls (0.082 vs 0.005, P=0.02).
Case-Control (n=17)
Does dipyridamole stress induce greater coronary sinus pH changes (indicating myocardial ischemia) in patients with hypertrophic cardiomyopathy compared to controls?
Coronary sinus pH monitoring during dipyridamole stress demonstrates a significantly greater pH decline in HCM patients compared to controls, providing evidence that chest pain in HCM is caused by myocardial ischemia.
Absolute Event Rate: 0.082% vs 0.005%
p-value: p=0.02
OBJECTIVES: The presence of angina pectoris and myocardial scarring in patients with hypertrophic cardiomyopathy (HCM) suggests that myocardial ischemia is a factor in the pathophysiology of the disease. The clinical evaluation of ischaemia is problematic in HCM as baseline electrocardiographic abnormalities are frequent and thallium-201 perfusion abnormalities correlate poorly with anginal symptoms. Coronary sinus pH measurement using a catheter mounted pH electrode is a validated sensitive technique for the detection of myocardial ischaemia. METHODS AND RESULTS: 11 patients with HCM and chest pain (eight men; mean (SD) (range) age 36 (11) (19-53) years) and six controls (two men; mean (SD) (range) age 49 (11) (31-62) years) with atypical pain and normal coronary angiograms were studied. Eight patients with HCM had baseline ST segment depression of > or = 1 mm and four had reversible perfusion defects during stress 201TI scintigraphy. A catheter mounted hydrogen ion sensitive electrode was introduced into the coronary sinus and pH monitored continuously during dipyridamole infusion (0.56 mg/kg over four min). The maximal change in coronary sinus pH during dipyridamole stress was greater in patients with HCM than in controls (0.082 (0.083) (0 to -0.275) v 0.005 (0.006) (0 to -0.012), P = 0.02). In six patients (four men; mean (SD) (range) age 29 (9) (19-40 years) the development of chest pain was associated with a gradual decline in coronary sinus pH (mean 0.123 (0.089)), peaking at 442 (106) s. There were no relations among left ventricular dimensions, maximal wall thickness, and maximum pH change. In patients with HCM there was a correlation between maximum pH change and maximum heart rate during dipyridamole infusion (r = 0.70, P = 0.02). CONCLUSION: This study provides further evidence that chest pain in patients with HCM is caused by myocardial ischaemia. The role of myocardial ischaemia in the pathophysiology of the disease remains to be determined but coronary sinus pH monitoring provides a method for quantifying and prospectively assessing its effects on clinical presentation and prognosis.
Elliott et al. (Thu,) conducted a case-control in Hypertrophic cardiomyopathy (n=17). Hypertrophic cardiomyopathy vs. Controls with atypical pain and normal coronary angiograms was evaluated on Maximal change in coronary sinus pH during dipyridamole stress (p=0.02). Patients with hypertrophic cardiomyopathy exhibited a significantly greater maximal change in coronary sinus pH during dipyridamole stress compared to controls (0.082 vs 0.005, P=0.02).
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: