Case Presentation: A 73 years old male who was recently diagnosed with metastatic squamous cell carcinoma of the right lung presented with worsening pressure like nonpositional central chest pain associated with some shortness of breath for the past two weeks. His other pertinent past medical history included COPD, mild coronary artery disease, myasthenia gravis and medically resolved nonischemic cardiomyopathy; recently diagnosed metastatic disease involving right cerebellum and left lobe of liver identified on MRI brain and MRA chest respectively. Repeat chest x ray, laboratory data were stable; with echocardiogram showing normal left ventricular function and no effusion. However the EKG demonstrated inferior lead ST elevations with cardiac enzymes repeatedly negative, nuclear stress test six months ago with no reversible ischemia and a prior heart catheterization with mild coronary artery disease. Given extensive metastatic disease and the above cardiovascular findings a PET-CT was done. This identified a focus of hypermetabolism in the apex of left ventricular wall consistent with an infiltrative process representing a metastatic lesion along with metastatic involvement of the right adrenal gland and proximal sigmoid colon. Patient desiring aggressive treatment underwent gamma knife radiation for cerebellar metastasis and was started on palliative chemotherapy with abraxane and carboplatin.
Discussion: Diagnosis of cardiac metastasis can be challenging due to nonspecific symptoms. In one of the largest autopsy series of over 1900 cancer patients, 8% had metastatic heart disease. There are rare reports in literature when myocardial metastasis has presented with myocardial infarction and stroke due to embolization; worsening congestive heart failure due to abnormal contractility or valvular abnormality and conduction defects. In our patient it was quite plausible that the isolated ST elevations were not ischemic changes and were attributed to ion channel disruption by mass lesion causing EKG repolarization abnormalities. This case is unique in that despite there being widespread metastasis to the brain, adrenals, liver; cardiac metastasis was not picked by routine imaging and PET-CT had to be utilized. Usually an echocardiogram and otherwise both cardiac MRI and CT noninvasively provide high resolution images however MRI is preferred.
Conclusions: Lung cancer is the most common cause of cardiac metastasis. Although the most commonly involved area is the pericardium, very rarely the myocardium can also be involved. It is important to keep cardiac metastasis as part of differential when working up cardiac causes of chest pain in the presence of ST elevations or conduction defects where advanced imaging in the form of PET-CT needs to be utilized.