Naser M. Ammash

Association of Atrial Fibrillation and Obstructive Sleep Apnea

Background—Obstructive sleep apnea (OSA) is associated with recurrent atrial fibrillation (AF) after electrocardioversion. OSA is highly prevalent in patients who are male, obese, and/or hypertensive, but its prevalence in patients with AF is unknown. Methods and Results—We prospectively studied consecutive patients undergoing electrocardioversion for AF (n=151) and consecutive patients without past or current AF referred to a general cardiology practice (n=312). OSA was diagnosed with the Berlin questionnaire, which is validated to identify patients with OSA. We also assessed its accuracy compared with polysomnography in a sample of the study population. Groups were compared with the 2-tailed t, Wilcoxon, and &khgr;2 tests. Logistic regression modeled the association of AF and OSA after adjustment for relevant covariates. Patients in each group had similar age, gender, body mass index, and rates of diabetes, hypertension, and congestive heart failure. The questionnaire performed with 0.86 sensitivity, 0.89 specificity, and 0.97 positive predictive value in our sample. The proportion of patients with OSA was significantly higher in the AF group than in the general cardiology group (49% versus 32%, P=0.0004). The adjusted odds ratio for the association between AF and OSA was 2.19 (95% CI 1.40 to 3.42, P=0.0006). Conclusions—The novel finding of this study is that a strong association exists between OSA and AF, such that OSA is strikingly more prevalent in patients with AF than in high-risk patients with multiple other cardiovascular diseases. The coinciding epidemics of obesity and AF underscore the clinical importance of these results.

Obstructive Sleep Apnea and the Recurrence of Atrial Fibrillation

Background—We tested the hypothesis that patients with untreated obstructive sleep apnea (OSA) would be at increased risk for recurrence of atrial fibrillation (AF) after cardioversion. Methods and Results—We prospectively obtained data on history, echocardiogram, ECG, body mass index, hypertension, diabetes, NYHA functional class, ejection fraction, left atrial appendage velocity, and medications in patients with AF/atrial flutter referred for DC cardioversion. Forty-three individuals were identified as having OSA on the basis of a previous sleep study. Data regarding the use of continuous positive airway pressure (CPAP) and recurrence of AF were obtained for 39 of these patients. Follow-up data were also obtained in 79 randomly selected postcardioversion patients (controls) who did not have any previous sleep study. Twenty-seven of the 39 OSA patients either were not receiving any CPAP therapy (n=25) or were using CPAP inappropriately (n=2). Recurrence of AF at 12 months in these 27 patients was 82%, higher than the 42% recurrence in the treated OSA group (n=12, P =0.013) and the 53% recurrence (n=79, P =0.009) in the 79 control patients. Of the 25 OSA patients who had not been treated at all, the nocturnal fall in oxygen saturation was greater (P =0.034) in those who had recurrence of AF (n=20) than in those without recurrence (n=5). Conclusions—Patients with untreated OSA have a higher recurrence of AF after cardioversion than patients without a polysomnographic diagnosis of sleep apnea. Appropriate treatment with CPAP in OSA patients is associated with lower recurrence of AF.

Coarctation of the aorta: outcome of pregnancy☆

OBJECTIVES The study sought to determine the outcome of pregnancy in women with coarctation of the thoracic aorta. BACKGROUND Patients with coarctation of the thoracic aorta are expected to reach childbearing age, but data on the outcome of pregnancy in this population are limited. METHODS The Mayo Clinic database was reviewed for women of childbearing age (> or =16 years old) with a diagnosis of aortic coarctation evaluated from 1980 to 2000. Spectrum of cardiovascular disease, surgical history, and obstetrical and neonatal outcomes were determined. RESULTS Fifty women with coarctation had pregnancies: 30 had coarctation repair before pregnancy, 10 had repair after pregnancy, 4 had repair both before and after pregnancy, and 6 had no history of repair. The 50 women had 118 pregnancies resulting in 106 births. There were 11 miscarriages (9%), 4 premature deliveries (3%), and 1 early neonatal death; 38 deliveries (36%) were by cesarean section. Of the 109 offspring, 4 (4%) had congenital heart disease. A patient with Turner syndrome died of a Stanford type A dissection at 36 weeks of pregnancy. Nineteen women (38%) were known to have hemodynamically significant coarctation during pregnancy (gradient > or =20 mm Hg). Fifteen women (30%) had hypertension during their pregnancy, 11 of whom (73%) had hemodynamically significant coarctation during that time (8 with native and 3 with residual/recurrent coarctation). CONCLUSIONS Major cardiovascular complications were infrequent but continue to be a source of concern for patients with coarctation who become pregnant. Systemic hypertension during pregnancy was common and related to the presence of a significant coarctation gradient.

Right Ventricular Strain for Prediction of Survival in Patients With Pulmonary Arterial Hypertension

BACKGROUND Pulmonary arterial hypertension (PAH) is a devastating illness of pulmonary vascular remodeling, right-sided heart failure, and limited survival. Whether strain-based measures of right ventricular (RV) systolic function predict future right-sided heart failure and/or death is untested. METHODS RV longitudinal systolic strain and strain rate were evaluated by echocardiography in 80 patients with World Health Organization group 1 pulmonary hypertension (PH) (72% were functional class [FC] III or IV). Survival status was assessed over 4 years. RESULTS All patients had a depressed RV systolic strain (-15% ± 5%) and strain rate (-0.80 ± 0.29 s(-1)). Of the parameters assessed, average RV free wall systolic strain worse than -12.5% identified a cohort with greater severity of disease (82% were FC III/IV), greater RV systolic dysfunction (RV stroke volume index 26 ± 9 mL/m(2)), and higher right atrial pressure (12 ± 5 mm Hg). Patients with an RV free wall strain worse than -12.5% were associated with a greater degree of disease progression within 6 months, a greater requirement for loop diuretics, and/or a greater degree of lower extremity edema, and it also predicted 1-, 2-, 3-, and 4-year mortality (unadjusted 1-year hazard ratio, 6.2; 2.1-22.3). After adjusting for age, sex, PH cause, and FC, patients had a 2.9-fold higher rate of death per 5% absolute decline in RV free wall strain at 1 year. CONCLUSIONS Noninvasive assessment of RV longitudinal systolic strain and strain rate independently predicts future right-sided heart failure, clinical deterioration, and mortality in patients with PAH.

Cerebrovascular events in adult patients with cyanotic congenital heart disease

OBJECTIVES We sought to determine the frequency of spontaneous cerebrovascular events in adult patients with cyanotic congenital heart disease and to evaluate any contributing factors. BACKGROUND Cerebrovascular events are a serious complication of cyanotic congenital heart disease in infants and children but are said to be uncommon in adults. METHODS Between 1988 and 1995, 162 patients with cyanotic congenital heart disease (mean age 37 years, range 19 to 70) were retrospectively evaluated for any well documented cerebrovascular events that occurred at > or = 18 years of age. Events related to procedures, endocarditis or brain abscess were excluded. RESULTS Twenty-two patients (13.6%) had 29 cerebrovascular events (1/100 patient-years). There was no significant difference between those with and without a cerebrovascular event in terms of age, smoking history, degree of erythrocytosis, ejection fraction or use of aspirin or warfarin (Coumadin). Patients who had a cerebrovascular event had a significantly increased tendency to develop hypertension, atrial fibrillation, microcytosis (mean corpuscular volume < 82) and history of phlebotomy (p < 0.05). Even when patients with hypertension or atrial fibrillation were excluded, there was an increased risk of cerebrovascular events associated with microcytosis (p < 0.01). CONCLUSIONS Adults with cyanotic congenital heart disease are at risk of having cerebrovascular events. This risk is increased in the presence of hypertension, atrial fibrillation, history of phlebotomy and microcytosis, the latter condition having the strongest significance (p < 0.005). This finding leads us to endorse a more conservative approach toward phlebotomy and a more aggressive approach toward treating microcytosis in adults with cyanotic congenital heart disease.

Bicuspid Aortic Valve Associated With Aortic Dilatation A Community-Based Study

Objective—This study was undertaken to examine the association between bicuspid aortic valve (BAV) and aortic dilatation in the community. The association between BAV and aortic dilatation has been reported predominantly in retrospective studies in patients mostly with valvular dysfunction or selected surgical patients from tertiary referral centers. An independent association of BAV and aortic dilatation in a community-based study has not been demonstrated. Methods and Results—In a geographically defined population of Olmsted County, Minnesota, residents with BAV (n=44, age 35±13 years) without hemodynamically significant obstruction or regurgitation and matched controls with normal tricuspid aortic valves were identified by transthoracic echocardiography. The two groups were compared with respect to measurements of the aorta. The BAV and control groups differed with respect to size of the aortic anulus (23.2±2.4 versus 21.6±2.4 mm;P =0.002), aortic sinus (33.5±4.6 versus 30.3±4.1 mm;P =0.0001), and proximal ascending aorta (33.3±6.5 versus 27.9±3.6 mm;P =0.0001). There was no difference in the size of the aortic arch (24.2±3.6 versus 25.3±3.4 mm;P =0.16). These differences were maintained when the groups were stratified by sex and blood pressure. The relationship between bicuspid aortic valve and aortic dilatation was maintained when adjusting for factors related to fluid mechanics and hemodynamics such as systolic blood pressure, diastolic blood pressure, left ventricular ejection time, and peak aortic valve velocity. Conclusions—In a community-based study, BAV is associated with an alteration of aortic dimensions even in the absence of hemodynamically significant aortic valve stenosis or regurgitation.

Outcome of the unoperated adult who presents with congenitally corrected transposition of the great arteries

OBJECTIVES The goal of this study was to determine the presentation and outcome of the unoperated adult with congenitally corrected transposition of the great arteries. BACKGROUND The presentation of this disorder and the outcome in unoperated adults have not been well defined. METHODS All unoperated patients > or =18 years old were evaluated for spectrum of disease, hemodynamic severity, timeliness of diagnosis and referral, and outcome. RESULTS Forty-four patients aged 20 to 79 years (mean, 44) were followed up to 144 months. In 29 (66%), the correct diagnosis was first made at age > or =18 years; the diagnosis was missed in seven of these patients in a prior cardiology consultation, despite cardiac imaging. Systemic atrioventricular valve (SAVV) regurgitation (grade > or =3/4) was noted in 26 patients (59%). Thirty (68%) had surgical intervention, including SAVV replacement in all, with no early mortality. Preoperatively, this subset had significant dysfunction of the systemic ventricle (SV) (ejection fraction [EF], 40 +/- 10%), and most had advanced symptoms (25 with ability index > or =2/4). In 16 (53%), SAVV regurgitation > or =3/4 and ventricular dysfunction had been documented for >6 months. The mean EF of the SV decreased significantly postoperatively (34 +/- 11%, p = 0.006). Four patients (13%) eventually required cardiac transplantation. Poor preoperative EF of the SV predicted eventual need for transplantation (p = 0.001). CONCLUSIONS Patients with unoperated congenitally corrected transposition of the great arteries are often misdiagnosed in adulthood and are referred late despite symptomatic SAVV regurgitation and significant SV dysfunction. Although excellent early surgical results can be achieved, significant residual dysfunction of the SV is common.

Intracranial aneurysms in patients with coarctation of the aorta: a prospective magnetic resonance angiographic study of 100 patients.

OBJECTIVE To determine the frequency of intracranial aneurysms (IAs) detected in patients with coarctation of the aorta (CoA) with use of magnetic resonance angiography. PATIENTS AND METHODS From January 1, 1980, to September 30, 2002, 277 adult patients with CoA were seen at the Mayo Clinic in Rochester, Minn, and were invited to participate in a study to detect IAs. Of these 277 patients (mean +/- SD age, 41.6 +/- 16.5; 70 men), 100 underwent cranial magnetic resonance angiography. RESULTS Ten patients had an IA (95% confidence interval, 5%-18%), with a mean diameter of 3.5 mm (range, 2.0-8.0 mm). The frequency of IA was significantly higher than that predicted in the general population (10% vs 2%; P < .001). One patient had surgical intervention. No clinical or geographical differences were found between patients with CoA and IA and patients with CoA and no IA. CONCLUSIONS The frequency of IA among patients with CoA is approximately 5-fold that of the general population. Although no risk factors were identified in this cohort, additional prospective evaluation is warranted. These data suggest that noninvasive cerebral imaging to screen for IA should be considered in patients with CoA.

Noncardiac surgery in Eisenmenger syndrome

OBJECTIVES The purpose of this study was to evaluate the morbidity and mortality associated with noncardiac surgery (NCS) in patients (pts) with Eisenmenger syndrome. BACKGROUND Noncardiac surgery in pts with Eisenmenger syndrome is associated with increased cardiovascular complications. METHODS Fifty-eight pts with Eisenmenger syndrome (17M, 41F aged 18 to 69 years (mean 41 years) who had been followed for up to 41.5 years (mean 9.3 years) were retrospectively evaluated for any NCS done at > or = 17 years of age. RESULTS Twenty-four pts had a total of 28 NCSs at an age of 17 to 55 years (mean 29 years) including 9 tubal ligations, 3 neurosurgeries, 3 cholecystectomies, 3 hysterectomies, 3 vasectomies, and 1 each spinal fusion, appendectomy, eye enucleation, hernia repair, hand surgery, tonsillectomy and therapeutic abortion. There were two deaths (7%), one following spinal fusion and the other following appendectomy at another institution. Fourteen of these NCSs were performed at our institution, including 11 under general anesthesia. The duration of anesthesia varied from 75 to 525 min (mean 165 min). All pts remained in sinus rhythm. The lowest systolic blood pressure (BP) ranged from 78 to 125 mm Hg. Of those 11 pts, 9 were extubated immediately after surgery and 2 needed dopamine. Ten patients were discharged without any complications, including 3 within 1 day of surgery. One death occurred 10 days following spinal fusion. This pt had the longest anesthesia (525 min) and an intraoperative systolic BP as low as 78 mm Hg. She also needed the largest fluid administration (6,475 cc) in addition to postoperative mechanical ventilation and dopamine. CONCLUSIONS Adult pts with Eisenmenger syndrome are at increased risk with NCS, but with current/modern techniques, the risk of death is less than previously thought. In the vast majority of cases, NCS can be undertaken without substantial morbidity, and early extubation is achievable. However, even with relatively minor surgery, significant complications, including death, can occur. Referral to major centers with expertise in the care of pts with Eisenmenger syndrome is advisable.

Partial Anomalous Pulmonary Venous Connection: Diagnosis by Transesophageal Echocardiography

OBJECTIVE This study sought to demonstrate that with proper technique, identification of the normal and abnormal pulmonary venous connection can be made with confidence using transesophageal echocardiography (TEE). BACKGROUND Partial anomalous pulmonary venous connection (PAPVC) is an uncommon congenital anomaly whose diagnosis has classically been made using angiography. METHODS We performed a retrospective review of all patients of all ages with PAPVC diagnosed at the Mayo Clinic who had undergone TEE because of either right ventricular volume overload or suspected intracardiac shunting by transthoracic echocardiography or intraoperatively. RESULTS A total of 66 PAPVCs were detected in 43 patients (1.5/patient); in 2 additional patients, TEE suggested, but did not diagnose, PAPVCs. Shortness of breath was the most common presenting symptom (42.2%), followed by heart murmur and supraventricular tachycardia. Right-sided anomalous veins were identified in 35 patients (81.4%), left-sided in 7 (16.3%) and bilateral in 1 (2.3%). There was a single anomalous connecting vein in 23 patients (53.5%), two in 18 (41.9%), three in 1 (2.3%) and four in 1 (2.3%). The connecting site was the superior vena cava (SVC) in 39 veins (59.1%), right atrial-SVC junction in 6 (9.1%), right atrium in 8 (12.1%), inferior vena cava in 1 (1.5%) and the coronary sinus in 2 (3.0%). Ten anomalous left pulmonary veins were connected by a vertical vein to the innominate vein (15.1%). Sinus venosus atrial septal defect (ASD) was the most common associated anomaly in 22 patients (49%), followed by ostium secundum ASD in 6 and patent foramen ovale in 4. Fifteen patients had an intact atrial septum. Thirty-one patients (68.8%) underwent surgical repair. PAPVC was confirmed in all patients, including the two whose TEE results were suggestive of PAPVC. All 49 PAPVCs detected by TEE preoperatively were confirmed at the time of operation. CONCLUSIONS TEE is highly diagnostic for PAPVC and can obviate angiography. Accurate anatomic diagnosis may influence the need for medical and surgical management. TEE should be performed in patients with right ventricular volume overload when the precordial examination is inconclusive.