Cath Lab Digest - October 2007 - (Page 14)

14 CASE REPORT OCTOBER 2007 Cerebral Vascular Accident Following a Pulmonary Embolism: Search for the Hidden Patent Foramen Ovale Alex Harrison, MD1, Ghalib Wahidi, MD2, Morton Kern, MD1 Division of Cardiology, Department of Medicine, University of California, Irvine, California; and 2 Department of Medicine, University of California, Irvine, California 1 Introduction We present a case of an 83-yearold man who developed a pulmonary embolism (PE) and then suffered a cerebral vascular accident (CVA) three days later as a result of an unsuspected patent foramen ovale (PFO). This example emphasizes the importance of considering and identifying a PFO as an unsuspected cause of CVA, especially in the setting of proven venous thromboembolic disease. Case Report An 83-year-old male with multiple medical problems was admitted to the hospital for intravenous antibiotic treatment of a severe lower extremity cellulitis. He suffered from longstanding diabetes mellitus and resultant chronic kidney disease with nephrotic range proteinuria and hypoalbuminemia. In addition, he was a former smoker and has mild chronic obstructive pulmonary disease (COPD) as well as heart failure with preserved left ventricular ejection fraction. On the third day of his hospitalization, he became progressively short of breath and hypoxic. Physical examination and routine testing did not readily identify a cause for his sudden dyspnea and hypoxia. Empiric treatment with diuretics and nebulized bronchodialators failed to improve his clinical situation. An echocardiogram was obtained and revealed a large right-to-left shunt across a PFO. The shunt was detected by color Doppler as well as agitated saline bubble study where the rightto-left flow was noted at rest without provocation or maneuvers. Figure 1 shows the agitated saline bubble study demonstrating opacification of the entire left atrium and left ventricle by bubbles shunting from the right atrium. His pulmonary arterial systolic pressure (PASP) was estimated at 44 mmHg, elevated from his prior baseline of 28 mmHg a few months prior. Left ventricular function was globally normal with an ejection fraction of 60-65%. His right heart function was also normal and without evidence of right ventricular hypertrophy or dilatation. Cardiology consultation was requested to assist in the evaluation and management of the right-to-left shunting across the PFO. At this time, physical exam revealed an elderly, ill-appearing male who was afebrile. Blood pressure was 150/80, pulse was 96 and regular, respiratory rate was 22 and his oxygen saturation was 93% on 4 liters of oxygen via nasal cannula. Neck exam revealed mild jugular venous distention estimated at 9 cm of water and no carotid bruits. Cardiac examination demonstrated a regular rate and rhythm with no appreciable murmurs, rubs, or gallops. Pulmonary exam revealed tachypnea, faint scattered wheezing diffusely, but otherwise clear to auscultation and percussion bilaterally. His abdomen was obese, but soft and with normal bowel sounds and no appreciable hepatosplenomegally. He had cellulitis of his lower extremities with bilateral upper and lower extremity 3+ pitting edema without any evidence of clubbing or cyanosis of the nails. His peripheral pulses were intact. Laboratory data revealed a hemoglobin of 9.8 mg/dL, a creatinine of 3 mg/dL, blood urea nitrogen (BUN) of 58 mg/dL, an albumin of 1.7 mg/dL, and a b-type natriuretic peptide (BNP) of 133 pg/mL. His electrocardiogram is shown in Figure 1. Apical four-chamber echocardiographic view demonstrating agitated saline bubble study where all four chambers are opacified, suggesting a right-to-left intracardiac shunt. Figure 2. ECG showing sinus tachycardia but otherwise normal. Figure 2. The chest x-ray revealed prominent pulmonary vasculature, but was otherwise unremarkable. An acute pulmonary embolism was highest on the differential, given the clinical picture of acute onset of dyspnea and hypoxia in a patient who has been bedridden in the hospital. In addition, despite being on prophylactic subcutaneous heparin against deep venous thrombosis (DVT), his nephrotic syndrome puts him at even higher risk because of his renal losses of protein C and S. A lower-extremity duplex ultrasound to evaluate for lower extremity DVT did not reveal any identifiable venous thrombus but was a difficult exam due to significant edema. A contrast computed tomography (CT) pulmonary angiogram was deferred given the high risk for developing contrast-induced nephropathy. A ventilation perfusion (V/Q) scan demonstrated a large right lower lobe perfusion defect suggestive of a PE. Anticoagulation treatment with intravenous heparin was started. The intra-atrial communication was determined to be a PFO. Prior echocardiograms were reviewed and did not have any findings of an intra-atrial communication or shunting by color Doppler when the patient had normal PASP. The PE was thought to increase pulmonary vascular resistance and thereby increase right atrial pressures, which opened a previously closed PFO and allowed for right-to-left shunting. Unfortunately, 3 days after the initiation of anticoagulation, the patient was observed to have right upper extremity weakness. A magnetic resonance imaging (MRI) of the brain showed an acute right parietal lobe infarct with surrounding edema measuring approximately 3.3 x 3.8 cm. After several days, the patient’s right upper extremity strength and respiratory status returned to his baseline. A repeat echocardiogram with agitated saline bubble study was obtained 10 days after the initiation of treatment with anticoagulation to reassess the degree of right-to-left

Table of Contents Feed for the Digital Edition of Cath Lab Digest - October 2007

Saints Medical Center Fibromuscular Dysplasia in Children and Adolescents Cerebral Vascular Accident Following a Pulmonary Embolism: Search for the Hidden Patent Foramen Ovale Contents Clinical Editor’s Corner Meetings Calendar CEU Education Center Radiation Tracking in the Cardiac Catheterization Lab Letter to the Editor Carotid Stenting: An update Release from Stent-jail: Beneficial Snow-Plowing? Patient Management Guidelines Searching for a Cardiovascular Position? Tips for Creating a ‘Stand-Out’ Resume Long-Term Implications of Short-Term Closure Decisions – The Evolution to Vascular Access Management and the Boomerang Catalyst System The Ten-Minute Interview with… Angie Bowles, RN, CCRN CMS Issues Final FY 2008 IPPS Rule ACVP• Membership Page Experience with a New Workhorse Guidewire Ask the Clinical Instructor: Q&A for Those New to Cath Lab A Glimpse of the Future of Clinical Education: Boston Scientific’s SimSuite Bus Visits Carnegie Institute 2007 Educational Fair Held at the Washington Hospital Center Research Update: Original Contribution Abstracts from The Journal of Invasive Cardiology What Do You Think? A Virtual Cath Lab Viewer (VCL): The Development of an Online 3D C-arm Simulator and Coronary Anatomy Viewer Clinical & Industry News Cost-Effectiveness of the Radial versus Femoral Artery Approach to Diagnostic Cardiac Catheterization

Cath Lab Digest - October 2007

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