A 64-year-old male with a medical history of hypertension, diabetes mellitus and hyperlipidemia and a chronic smoker presented with complaints of chest pain which was sharp, continuous in nature and was aggravated by slight walking or lifting of heavy loads. The patient also had complaints of shortness of breath of Grade 4 according to the Medical Research Council (MRC) Dyspnoea Scale []. He had a body mass index (BMI) of 25.8 Kg/m2. The baseline HbA1c% value was 10.8 gm%. He underwent coronary angiography at the discretion of the concerned cardiologist. A diagnosis of Acute Coronary Syndrome (ACS) with Non-ST elevation Myocardial Infarction (NSTEMI) with an occlusion of 99% in the left circumflex artery (LCX) was made. Percutaneous Coronary Angioplasty (PTCA) was performed on the same day with the placement of one everolimus eluting coronary stent in the LCX.\nA loading dose of 180 mg of ticagrelor was given to the patient just before the PTCA was performed. A thrombolysis in myocardial infarction (TIMI) 3 flow was achieved post the procedure. Blood flow distal to the stent was achieved and the procedure was concluded successfully. The post procedural ejection fraction (EF) was 45%. Post procedural electrocardiogram (ECG) was also performed and it showed a QTc of 402 ms with atrial fibrillation and poor progression of the R wave in leads V4 and V5 (). He got discharged after 2 days with an advice of 180 mg ticagrelor, 75 mg aspirin, 20 mg atorvastatin, 25 mg metoprolol, 25 mg spironolactone, 10 mg furosemide and 1000 mg of metformin daily. He was advised to visit the out-patient department (OPD) of Cardiology after 2 months or the ED in case of any emergency.\nThe patient came to the OPD after 1.5 months with complaints of severe shortness of breath (MRC Dyspnoea Scale Grade 5) along with infrequent bouts of coughs. Vitals were measured and the blood pressure was 104/60 mm Hg, with the pulse being 68/min. On auscultation, no bronchopulmonary abnormality could be inferred. Bilateral clear breath sounds were obtained. A BMI of 24.6 Kg/m2 was recorded. In view of ticagrelor induced dyspnea, ticagrelor was discontinued and 75 mg clopidogrel once daily was started while rest of the medications were kept unchanged. An ECG was obtained and it showed a QTc of 468 ms (16.4% increase) with biphasic T wave in Lead III (). He was advised to visit the Cardiology OPD after 1 month or the ED in case of any emergency.\nThe patient came back after one month for follow-up. He had no complaints of shortness of breath or cough this time. Vitals were measured and blood pressure was 114/78 mm Hg with a pulse rate of 66/min. HbA1c% came out to be 9.6 gm%. An ECG was done and it showed a drastic reduction of the QTc to 425 ms (9.2% reduction) () with slight ST elevation in leads V4 and V5. An echocardiography was also performed and the EF came out to be 50%.
In May of 2016, a 55-year-old male with history of hypertension, hyperlipidemia, and coronary artery disease (CAD) status after angioplasty of left anterior descending (LAD) artery 2 years ago presented to the emergency room (ER) with substernal chest pain. His cardiac enzymes were not elevated and electrocardiogram (EKG) showed normal sinus rhythm at a rate of 62 bpm with borderline AV conduction delay and right bundle branch block (RBBB) pattern (). The patient was only taking aspirin and had discontinued his statin due to muscle ache and metoprolol because of fatigue. His chest pain was relieved with sublingual nitroglycerin in the ER. In view of his significant history of CAD and typical anginal symptoms, patient underwent cardiac catheterization. It revealed 90 percent stenosis of the left mid circumflex coronary artery which was successfully stented with a drug-eluting stent. Right coronary artery (RCA) showed 50–60% stenosis while LAD showed patent stent. The patient recovered very well. After calculating the GRACE score, the patient was discharged on aspirin and ticagrelor as per the ACC guidelines. He was also prescribed rosuvastatin and metoprolol. Two months after PCI, the patient presented to his primary cardiologist due to worsening fatigue and intermittent dizziness. His metoprolol was stopped. In November, 2016, he was brought by emergency squad to the hospital due to worsening dizziness and diaphoresis at rest. He denied any h/o chest pain, palpitations, nausea, or loss of consciousness. The patient had stopped ticagrelor 1 day prior to this admission since he ran out of it. The patient requested a second opinion on this admission. On physical examination, his blood pressure was 126/66 mmHg and heart rate was regular at 42 beats per minute. The neck was supple with no carotid bruits and cardiac auscultation revealed 2/6 ejection systolic murmur in the left sternal border. Patient's EKG revealed second-degree type II atrioventricular (AV) block which was new (). His cardiac enzymes, thyroid stimulating hormone, serum potassium, and magnesium were within normal range. The patient did not receive ticagrelor further during the admission. Cardiac catheterization revealed RCA stenosis of 60–70% but no intervention was required as this was not the cause of the new onset heart block. We considered starting patient on oral theophylline on admission had the heart block not resolved within 24 hours. His second-degree heart block resolved 2 days after discontinuation of ticagrelor and his EKG showed sinus bradycardia (heart rate = 54 bpm) with borderline AV conduction delay with RBBB pattern () which was similar to his baseline EKG. Clopidogrel was started as an alternative P2Y12 platelet receptor inhibitor and aspirin was continued. He was discharged after an event monitor was placed.