The patient underwent coronary angiography and later CT angiography. The diagnosis was "Apical hypertrophic cardiomyopathy with coronary fistulas into the left ventricle" (see videos of coronary angiography showing ectaticand tortuous left coronary system with contrast emptying into left ventricular cavity. Also CT image showing apical hypertrophy with obtuse marginal branch of the circumflex draining into hypertrophied myocardium).
Coronary fistulas communicating with cardiac chambers (also known as coronary-cameral fistulae) are rare and are usually noted incidentally on coronary angiography with an incidence of up to 0.3%. Such fistulae have been described as arterio-luminal, where there is direct and focal communication with the cardiac chamber concerned, or arterio-sinusoidal, as in this case where arterial blood ommunicates with the cardiac chambers via a sinusoidal network. The vast majority (90%) of cameral fistulae communicate with the right-sided chambers of the heart while a minority drain to the left side of the heart or to both. Inducible ischemia is thought to occur as a result of a coronary steal phenomenon. Dyspnea may be due to volume overload in the case of large fistulae (1)
Dresios et al. reported on an 83-year-old woman with electrocardiographic abnormalities and a history of arterial hypertension and paroxysmal atrial fibrillation who was diagnosed with apical hypertophic cardiomyopathy and multiple coronary AV fistulae. .In an accompanying review of the literature they cite seven publications of coronary –LV fistulae with hypertrophic cardiomyopathy. Hypertrophic cardiomyopathy and coronary artery–cardiac chamber fistulae could simply co-exist or there could be a causative relationship between the two conditions. Even if a causative relationship exists, the pathophysiological background remains unclear. The apical hypertrophy could be the result of chronic LV volume overload through the coronary artery–LV shunt or could be the cause of multiple coronary microfistulae, possibly due to myocardial fiber disarray known to be present in this condition.(2) The apical hypertrophy may be confused with non-compaction of the left ventricle where prominent vascular sinusoids persist from embryonic life and fail to be compacted into normal ventricular myocardium. Other imaging modalities such as MR and CT may help in differentiating the two conditions.
There are no established treatment recommendations. The majority however recommend beta blockers.
Padfield et al: European Journal of Echocardiography (2009) 10, 718–720
Dresios et al. European Journal of Echocardiography (2010) 11, E9