Chaliki, Hari P.

Background and Purpose— Detection of an intracardiac shunt is frequently sought during the evaluation of patients with cryptogenic ischemic stroke and agitated saline intravenous injection, or “bubble study” (BS), is performed in most cases. We present the first attempt to identify the clinical features in patients who had cerebral ischemic events with BS. Methods— Using a list serve established by the American Academy of Neurology, a member posted a question regarding the safety of BS in patients with patent foramen ovale. A standardized questionnaire was used to gather data about patients with cerebral ischemic events, details of each case were reviewed, and the findings pooled. Results— Five patients with ischemic complications of BS (all female, aged 42 to 90 years) were identified from 4 institutions, 3 ischemic strokes and 2 transient ischemic attacks. Events occurred either during or within 5 minutes of BS. Early brain MRIs confirmed acute infarction in 3, including one who had transient symptoms. MRI infarct volumes were small, and deficits were mild in those who developed stroke. Diagnostic evaluation revealed a patent foramen ovale alone in one case, a pulmonary arteriovenous malformation in one case, and a patent foramen ovale and/or pulmonary shunt in 3 cases. Conclusions— Ischemic cerebrovascular complications can occur in patients who undergo BS and are associated with the presence of cardiac or pulmonary shunts. The true incidence and degree of disability remains unknown, and further study is indicated to assess the impact of technical differences in BS methodology. Novel methods to promote physician communication such as the use of electronic list serves may reduce barriers to reporting of drug, technique, or device complications and should be explored to identify rare complications that otherwise will likely go unappreciated.

Background— Left ventricular dysfunction is an indication for aortic valve replacement (AVR) in patients with severe aortic regurgitation (AR). However, the postoperative outcome of patients with severe AR and a markedly low ejection fraction (EF) is not known. Methods and Results— The study group consisted of a total of 450 patients who had AVR for isolated AR between 1980 and 1995. Patients with markedly reduced left ventricular function (EF <35%, LoEF, n=43) were compared with those with moderate reduction in left ventricular function (EF 35% to 50%, MedEF, n=134) and those with normal left ventricular function (EF ≥50%, Nl EF, n=273). The operative mortality rate was higher with LoEF (14%) than with MedEF and Nl EF (6.7% and 3.7%, respectively, P =0.02). At 10 years, 41%±9% of LoEF patients had survived compared with 56%±5% and 70%±3% of MedEF and Nl EF patients, respectively ( P <0.0001). Congestive heart failure occurred at 10 years in 25%±9% with LoEF compared with 17%±4% and 9%±2% with MedEF and NL EF, respectively ( P <0.003). Postoperative EF improved by 4.9%±13.8% in the LoEF group and by 4%±11.9% in the MedEF group compared with −2.3%±10.9% in the Nl EF group ( P <0.002 and P <0.0001, respectively). Conclusions— Patients with severe AR and markedly low EF incur excess operative mortality rates, postoperative mortality rates, and congestive heart failure after AVR. However, postoperative EF improves markedly, and most patients enjoy a long postoperative survival without recurrence of heart failure after AVR; thus they should not be denied the benefits of AVR.