A 69-year-old man presents to his primary care provider for a general checkup. He has a medical history of type 2 diabetes mellitus, hypertension, depression, obesity, and a myocardial infarction 7 years ago. The patient's prescribed medications are metoprolol, aspirin, lisinopril, hydrochlorothiazide, fluoxetine, metformin, and insulin. The patient has not been filling his prescriptions regularly and can not remember what medications he has been taking. His temperature is 99.5°F (37.5°C), pulse is 96/min, blood pressure is 180/120 mmHg, respirations are 18/min, and oxygen saturation is 97% on room air. Laboratory values are obtained and the results are shown below:

Serum:
Na+: 139 mEq/L
K+: 4.3 mEq/L
Cl-: 100 mEq/L
HCO3-: 24 mEq/L
BUN: 7 mg/dL
Glucose: 170 mg/dL
Creatinine: 1.2 mg/dL

Which of the following cardiac findings would be expected on physical exam?
Heart sound after S2
Holosystolic murmur at the apex
Heart sound before S1
Fixed splitting of S1 and S2
Heart sound before S1
This patient who presents with poorly managed hypertension over a long period of time most likely has compensatory hypertrophy of the heart. The most likely heart sound in this patient is an S4 gallop that occurs immediately before S1.

Chronic hypertension that is poorly controlled can lead to concentric hypertrophy of the heart. This adaptive mechanism creates a stiff and non-compliant left ventricle. When blood enters this stiff ventricle, the typical sound heard is an S4 heart sound which is heard right before S1. This sound represents the atrial kick that pushes blood against a non-compliant left ventricle in the last phase of diastole. Treatment is by meticulous control of the underlying cardiac pathophysiology such as hypertension.

Kino et al studied the relationship between the S1 and S4 heart sounds in aging patients. They found that an S4 heart sound can be missed in cases of prominent S1 splitting. They recommend studying heart sounds in order to not accidentally miss an S4 finding.

Incorrect Answers:
Answer A: Fixed splitting of S1 and S2 describes an atrial septal defect. The atrial septic defect allows blood to communicate between both sides of the heart and equalizes atrial pressures. Asymptomatic patients may not need treatment but surgical repair of the defect should be performed in symptomatic cases.

Answer B: A heart sound after S2 suggests a S3 heart sound which would be found in fluid-overloaded states such as heart failure. This post-systolic gallop is the result of incomplete emptying of the ventricle prior to the start of diastole so that the blood from the atria falls against an already full chamber. Treatment is with diuresis and treatment of the underlying heart failure.

Answer D: A holosystolic murmur heard at the apex describes mitral valve regurgitation. This would be possible if a papillary muscle had ruptured in an acute myocardial infarction. Treatment is with mitral valve replacement in symptomatic patients.

Answer E: A normal S1 and S2 is possible but is less likely given this patient's long-standing history of poorly managed hypertension. Hypertension usually causes concentric hypertrophy of the ventricle and thereby leads to increased resistance to diastolic filling.

Bullet Summary:
An S4 heart sound is created by blood entering a stiff and non-compliant left ventricle and is often heard in patients with long-standing hypertension.