Unilateral pulmonary edema secondary to idiopathic rupture of mitral chordaea tendinae.

To the Editor: Pulmonary edema is an uncommon form of unilateral pulmonary infiltrate. (1) Rupture of mitral chordae tendineae may result in severe mitral regurgitation, and may cause pulmonary edema. Although unilateral pulmonary edema (UPE) secondary to mitral regurgitation has been reported in the literature, (2) to the best of our knowledge, UPE secondary to idiopathic rupture of the mitral valve has not been reported previously. We report the case of a patient with unilateral pulmonary edema secondary to idiopathic rupture of mitral chordae tendineae.

A 65-year-old male was admitted with the sudden onset of progressive dyspnea. His previous medical history was remarkable for hypertension. On examination, the patient was found to be in severe respiratory distress. Vitals revealed a blood pressure of 100/60 mm Hg, pulse rate of 120, axillary temperature of 36.5[degrees]C, and a respiratory rate of 34. Pulmonary auscultation revealed absent breath sounds over the lower half of the right lung and diminished breath sounds over the upper half of the right lung with rales. Left lung auscultation was normal. A pansystolic apical murmur radiating to the axilla was detected. Electrocardiogram showed normal sinus rhythm without any sign of coronary ischemia. Chest x-ray confirmed unilateral right-sided pulmonary edema with mild pleural effusion (Fig. 1). The patient's biochemical values, including D-Dimer, were within normal limits. Transthoracic echocardiogram revealed a rupture of chordae tendineae, severe mitral regurgitation, left atrial enlargement (45 mm), mild left ventricular hypertrophy, mild tricuspid regurgitation and a normal ejection fraction of 60%. The pulmonary artery systolic pressure was 30 mm Hg. Transesophageal echocardiography showed rupture of the mitral chordae tendineae and severe mitral regurgitation. During color Doppler imaging, the mitral regurgitant jet was noted to be directed toward the left atrial appendage. The jet was then turned to the right side and headed directly to the right pulmonary vein ostia. The patient was treated with IV diuretics, morphine, ACE inhibitor, and IV nitrate. After medical treatment, his clinical status and chest x-ray improved. Once stable, he underwent left heart catheterization that showed normal epicardial coronary arteries and severe mitral regurgitation.

Congestive heart failure (CHF) is the most common etiology of pulmonary edema. Pulmonary involvement is bilateral in almost all patients with CHF. On x-ray, congestive heart failure usually presents with bilateral opacities in the central and basal zones of the lungs. Although UPE secondary to CHF has been reported, (1) it is not common.

[FIGURE 1 OMITTED]

Pathophysiologically, pulmonary edema results from a rise in the pulmonary capillary hydrostatic pressure, altered capillary permeability, a decrease in oncotic pressure or lymphatic insufficiency. Among these factors, increase in pulmonary capillary hydrostatic pressure is the most likely mechanism in our patient. We think that the flow-jet of mitral insufficiency selectively directed toward the right upper pulmonary vein might be causing right-sided UPE in our patient. As in our patient, most cases of heart failure presenting with UPE involve the right lung. (2-4) This may be due to inferior lymphatic drainage of the right lung by the small-caliber right bronchomediastinal trunk in comparison to that of the left lung carried out by the large-caliber thoracic duct.

In conclusion, although unilateral pulmonary edema secondary to mitral regurgitation has been reported, to the best of our knowledge, this is the first reported case of unilateral pulmonary edema secondary to idiopathic rupture of mitral chordae tendineae.

Bekir S. Cebeci, MD

Ejder Kardesoglu, MD

Fethi Kilicaslan, MD

Ata Kirilmaz, MD

Eralp Ulusoy, MD

Namik OZMEN, MD

Omer Uz, MD

Mehmet Dincturk, MD

Department of Cardiology

Haydarpasa Training Hospital

Gulhane Military Medical Academy

Istanbul, Turkey

References

1. Nitzan O, Saliba WR., Goldstein LH, et al. Unilateral pulmonary edema: a rare presentation of congestive heart failure Am J Med Sci 2004;327:362-364.

2. Roach JM, Stajduhar KC, Torrington KG. Right upper lobe pulmonary edema caused by acute mitral regurgitation diagnosis by transesophageal echocardiography. Chest 1993;103:1286-1288.

3. Calenoff L, Kruglik GD, Woodruff A. Unilateral pulmonary edema. Radiology 1978; 126: 19-24.

4. Kramer MR, Melzer E, Sprung CL. Unilateral pulmonary edema after intubation of the right main stem bronchus. Crit Care Med 1989;17:472-474.