Cardiac manifestations of Grave's disease would include all of the folloing except -

The most common cardiovascular manifestation of Graves' disease is sinus tachycardia, often associated with palpitations, occasionally caused by supra-ventricular tachycardia. The high cardiac output produces a bounding pulse, widened pulse pressure, and an aoic systolic murmur and can lead to worsening of angina or hea failure in the elderly or those with preexisting hea disease. Atrial fibrillation is more common in patients >50 years of age. The Means-Lerman (pleuropericardial) scratch is a mid-systolic scratching sound best heard over the upper pa of the sternum or second left intercostal space at the end of expiration .This results from the rubbing of the pericardium against the pleura in the context of hyperdynamic circulation and tachycardia, and may mimic the sound of a pericardial rub . Reference : page 2294 Harrison's Principles of Internal Medicine 19th edition