Usefulness of Oximetry Paradoxus to Diagnose Cardiac Tamponade.

Although echocardiography is usually diagnostic of cardiac tamponade, it may not be readily available at the point-of-care. We sought to develop and validate a measurement of respirophasic variation in the amplitude of pulse oximetry plethysmographic waveforms as a diagnostic tool for cardiac tamponade. Pulse oximetry plethysmographic waveforms were recorded, and the ratio of maximum-to-minimum measured amplitude of these waveforms from one respiratory cycle was calculated by blinded observers. Ratios from 3 consecutive respiratory cycles were then averaged to derive an "oximetry paradoxus" ratio. Cardiac tamponade was independently confirmed or excluded according to a "blinded" objective interpretation of echocardiography or right heart catheterization. Seventy four subjects were enrolled (51% men; mean age 54 ± 15 years); 19 of whom had cardiac tamponade. Oximetry paradoxus area under the curve for diagnosis of cardiac tamponade was 0.90 (95% confidence interval, 0.84 to 0.97); its diagnostic performance was superior to sphygmomanometer-measured pulsus paradoxus (area under the curve difference = 0.16, p = 0.022). In a derivation cohort (n = 37; tamponade, 9 cases), 3 diagnostic oximetry paradoxus thresholds were identified and validated in an independent validation cohort (n = 37; tamponade, 10 cases): 1.2 (100% sensitivity, 44% specificity), 1.5 (80% sensitivity, 81% specificity), and 1.7 (80% sensitivity, 89% specificity). Furthermore, oximetry paradoxus was significantly reduced after draining pericardial fluid. In conclusion, we defined and validated oximetry paradoxus as a simple and ubiquitous point-of-care test to diagnose cardiac tamponade using respirophasic changes in pulse plethysmography waveforms. This test can aid in identifying patients with cardiac tamponade, thus expediting confirmatory testing and life-saving treatment.

Sex Differences in Atrial Fibrillation-Update on Risk Assessment, Treatment, and Long-Term Risk.

PURPOSE OF REVIEW: Atrial fibrillation (AF) is a growing health problem worldwide. While the disease plagues both men and women, this arrhythmia does not affect both sexes equally. Women are more likely to have major adverse outcomes such as stroke and its sequela; however, recent data on stroke prevention show improving outcomes. The purpose of this review of the recent literature is to summarize important updates on risk scores and management of patients with AF. RECENT FINDINGS: It has been well known that women have a higher risk of strokes than men when untreated or when treated with warfarin. Current risk scores emphasizing new risk factors such as the higher risk of strokes in women have been incorporated into clinical guidelines. However, with the use of direct oral anticoagulants, this sex disparity on stroke is no longer seen and women have less major bleeding than men. The use of cardiac glycosides is associated with increased incidence of breast cancer, and this medication is used more in women. Procedural complications for the management of AF are higher in women. The study of the pathophysiology of AF and its management is a rapidly evolving area of cardiovascular medicine. Sex-specific data is necessary to achieve advances in the field and improve the outcomes in both men and women.

A comparative assessment of coronary artery calcification on chest CT scans of patients referred to a cardio-oncology clinic.

BACKGROUND: The presence and burden of coronary artery calcium (CAC) is a strong predictor of cardiovascular events. In an effort to gain insight into the utility of CAC for coronary artery disease (CAD) screening in cancer patients with heart disease, we sought to determine the presence and burden of CAC detected on routine chest CT in patients referred to a cardio-oncology clinic, comparing them to a conventional cardiology clinic with the general population as controls. METHODS: Patients from the cardio-oncology clinic, general cardiology clinic, and the general clinic population at Rush University Medical Center who had a chest CT as part of their previous treatment were identified. Each CT scan was evaluated for presence, extent, and severity of CAC by 3 independent readers. RESULTS: In multivariate analysis, when compared with cardio-oncology clinic, CAC was more prevalent in the CT scans of cardiology patients (p = 0.04), but not the general clinic population (p = 0.5); CAC extent (p = 0.05) and severity (p = 0.05) was significantly higher in the cardiology patients but the extent (p = 0.05) and severity (p = 0.92) was similar in the general clinic population. CONCLUSION: Despite being matched by age and sex, controlling for other major cardiovascular risk factors, patients referred to our cardio-oncology clinic had similar and less prevalent/severe CAC burden compared with the general population and conventional cardiology clinics respectively. Whether this translates to less utility of CAC for CAD screening, or to less overall coronary events in a cardio-oncology clinic, is of interest.

Emerging, noninvasive surrogate markers of atherosclerosis.

Noninvasive surrogate markers of atherosclerosis allow the physician to identify subclinical disease before the occurrence of adverse cardiovascular events, thereby limiting the need to perform invasive diagnostic procedures. Imaging modalities, such as carotid artery ultrasound, two-dimensional echocardiography, coronary artery calcium imaging, cardiac magnetic resonance imaging, ankle-brachial indices, brachial artery reactivity testing, and epicardial coronary flow reserve measurements, provide information that may improve the predictive value of a person's risk of developing clinically significant atherosclerotic disease. Newer imaging modalities have also emerged to bring insight into the pathophysiology and treatment of atherosclerosis.