Sodium and its multiorgan targets.

Case Presentation: A 66-year-old retired man presented to his physician with complaints of shortness of breath and weight gain over 1 week’s time during a recent cruise. He was not short of breath in the supine position, although his neck veins were distended. The blood pressure was 196/ 104 mm Hg; his heart rate was 92 bpm; and his cardiac rhythm was normal. He had a large habitus and was 76 in tall and 248 lb, which was 27 lb heavier than when he was evaluated 6 weeks previously in the office. The lungs revealed fine crackling rales bilaterally and posteriorly, but no wheezes or other sounds were noted. A fourth heart sound was heard at the apex. The ECG revealed left atrial abnormality and left ventricular hypertrophy with a normal sinus rate and rhythm. The echocardiogram confirmed left ventricular hypertrophy, increased left atrial size, and evidence of impaired diastolic function, and the left ventricular ejection fraction was 32%. Pulse wave velocity and aortic distensibility were impaired. There was severe 4 bilateral edema of both lower extremities to the knees. Although the hemogram was normal, his blood urea nitrogen and creatinine concentrations were 28 and 1.2 mg/dL, respectively. The urinalysis revealed 4 proteinuria, and a 24-hour urine collection for sodium content (at the time when his appointment was made) was 13 g.