Our patient's diagnosis has been well defined by the history, bedside findings and the non-invasive laboratory assessment. The primary reason for cardiac catheterization in a patient with a dilated cardiomyopathy is to evaluate coronary anatomy. In some patients, multivessel coronary artery disease simulates cardiomyopathy by causing silent infarction and chronic myocardial ischemia. The term hibernating myocardium has been applied to viable, but poorly perfused, and poorly contractile myocardium.
Left coronary angio
This is a still-frame of the left coronary artery angiogram in the left anterior oblique cranial view in our patient. The large left main vessel divides into its two major branches, the left anterior descending, or LAD, and the circumflex coronary artery. Minor diffuse changes are noted in the area of the mid left anterior descending with no significant focal stenosis. The remainder of the left coronary system is essentially normal. In the real-time study that follows, note the widely separated, elongated and spindly appearance of the vessels as they surround the markedly enlarged left ventricle.
Right coronary angio
This is a still-frame of the right coronary artery angiogram in the right anterior oblique view. Two right ventricular branches are well seen. The vessel is large in caliber and normal in appearance. The apparent distal narrowing of the right coronary is a bend in the vessel and does not represent obstructive disease. This was verified in other views.
Left ventriculography
During catheterization, left ventriculography may not be necessary if left ventricular function has been well defined by non-invasive imaging techniques such as echocardiography or other modalities. Invasive left ventriculography may be contraindicated in the presence of renal insufficiency or a mural thrombus. It was safely carried out in our patient.
Left ventriculogram
This is a systolic still-frame of the left ventriculogram in the right anterior oblique view from our patient. The tip of the pigtail catheter is in the left ventricle. Contrast material has been injected into the left ventricle and is seen in the ascending aorta as a normal result of ventricular ejection. Note the increased systolic volume of the left ventricle. In the real-time study that follows, note the global impairment of left ventricular contractility. The ejection fraction is estimated at fifteen to twenty percent. Note also the arrow labeled MR. While difficult to see, the real-time study will demonstrate mitral regurgitation in this area. Contrast material will be seen moving from the left ventricle to the left atrium during systole.
Cath data
This is our patient's left ventricular pressure tracing. It clearly shows an elevated end diastolic pressure. The right ventricular end diastolic pressure was also elevated. These findings reflect marked biventricular diastolic dysfunction. Other findings at catheterization included a very low ejection fraction and cardiac index, indicating severe left ventricular systolic dysfunction. There was also elevation of right heart pressures with a moderate increase in pulmonary pressure and pulmonary vascular resistance.
Our patient's cath discussion
Our patient's cardiac catheterization has confirmed the diagnosis of idiopathic dilated cardiomyopathy. There was no evidence of significant underlying coronary artery disease. His severe heart failure is due to both systolic and diastolic dysfunction. Systolic dysfunction is reflected by a very low ejection fraction diastolic dysfunction is reflected by very high end diastolic filling pressures.
Additional testing
Additional testing may include cardiac magnetic resonance imaging for the assessment of tissue characterization. Endomyocardial biopsy may be performed in cases of unexplained heart failure.