THE CASE
A 44-year-old man with a history of morbid obesity reestablished care in our clinic. He had been treated in our health care system about 5 years previously, and prior lab testing showed a total cholesterol of 203 mg/dL; triglycerides, 191 mg/dL; high-density lipoprotein (HDL), 56 mg/dL; and low-density lipoprotein (LDL), 109 mg/dL. At that time, he weighed 299 lbs (BMI, 39.4). He then started a strict ketogenic diet and a regular exercise program (running ~ 16 miles per week and lifting weights), which he maintained for several years. He had experienced remarkable weight loss; upon reestablishing care, he weighed 199 lbs (BMI, 26.33).
However, lipid testing revealed a severely elevated total cholesterol of 334 mg/dL; LDL, 248 mg/dL; HDL, 67 mg/dL; and triglycerides, 95 mg/dL. He was advised to start statin therapy and to stop his ketogenic diet, but he was hesitant to take either step. He elected to have his lab work reevaluated in 6 months.
About 4 months later, he presented with new and increasing burning pain in his mid chest and upper abdomen. He rated the pain 6/10 in severity and said it occurred during exertion or at night when lying down. Resting would relieve the pain. Reduced intake of spicy foods and caffeine had also helped. He denied dyspnea, diaphoresis, palpitations, or nausea.
The patient was a nonsmoker but did have a strong family history of cardiovascular disease. His vital signs and physical examination were unremarkable, apart from mild epigastric and periumbilical tenderness on palpation.
THE DIAGNOSIS
The patient’s chest pain had features of both gastroesophageal reflux disease (GERD) and coronary artery disease (CAD) with exertional angina. His high-fat diet, nightly symptoms, and the partial relief he achieved by cutting back on spicy foods and caffeine suggested GERD, but the exertional nature of the chest pain and gradual relief with rest was highly suggestive of angina, so an outpatient electrocardiogram treadmill stress test was ordered.
The stress test was markedly abnormal, showing worsening ST depressions and T-wave inversions with exertion, and he experienced chest pain during testing. An urgent left heart catheterization was performed, showing severe multivessel CAD. He subsequently underwent 3-vessel coronary artery bypass grafting. A familial hypercholesterolemia panel failed to reveal any significant variants.
As a result of these findings, the patient received a diagnosis of severe ketogenic diet–associated hypercholesterolemia and early-onset CAD.
Continue to: DISCUSSION