Spontaneous Coronary Artery Dissection in a 26-Year-Old-Male Soldier.

Spontaneous coronary artery dissection (SCAD) is an uncommon cause of acute coronary syndromes, which has been gaining increased recognition with the routine use of coronary angiography and intravascular imaging techniques in patients presenting with ST-elevation myocardial infarction. Here we report the case of a healthy, 26-year-old active-duty male presented to Tripler Army Medical Center for evaluation of acute onset and worsening chest pain that occurred shortly after participating in an Army physical fitness test. His initial EKG demonstrated a myocardial injury pattern with ST elevations in leads V1-V4. Invasive angiography revealed thrombotic occlusion of the proximal left anterior descending coronary artery with no evidence of atherosclerotic disease by intravascular ultrasound imaging. SCAD was suspected, and this diagnosis was confirmed after eptifibatide-induced propagation of the dissection plane resulting in recurrence of his index chest pain. To our knowledge, this is the first reported case of SCAD in the active-duty military population. SCAD is a rare, but important, cause of acute coronary syndromes that must be recognized by military providers as it necessarily precludes further military service.

Exclusion of left atrial appendage thrombus using single phase coronary computed tomography as compared to transesophageal echocardiography in patients undergoing pulmonary vein isolation.

Background. Transesophageal echocardiography (TEE) is used for the evaluation of the presence of left atrial appendage (LAA) thrombus prior to pulmonary vein isolation (PVI), while coronary computed tomography angiography (CCTA) is used for anatomic mapping during PVI. Methods. We compared the diagnostic performance of single phase CCTA to TEE in excluding the presence of LAA thrombus in patients undergoing PVI in 172 subjects performed during index hospitalization. Results. The mean age was 51 ± 13 years, a median CHADS2 score of 1 [IQR25,75 0,1, range 0-3] and a mean periprocedural INR of 2.1 ± 0.6. The prevalence of an LAA filling defect on single phase CCTA was 9.3% (6/183) and on TEE was 1.2% (2/183). Sensitivity, specificity, positive predictive value, and negative predictive value were 100% (95% CI, 19.8-100%), 91.8% (95% CI, 94-99%), 12.5% (95% CI, 60-76%), and 91.8% (95% CI, 97-100%) for the detection of LAA filling defect, respectively. Conclusion. Given the utility of a preprocedural single phase CCTA for the performance of PVI, the absence of a filling defect negates the need for a subsequent TEE as an adjunct for exclusion of LAA thrombus.

Computed tomography coronary angiography versus stress myocardial perfusion imaging for risk stratification in patients with high occupational risk.

PURPOSE: To compare the performance of myocardial perfusion imaging (MPI) versus cardiac computed tomographic angiography (CCTA) in patients with a low pretest likelihood of obstructive coronary artery disease and high-risk occupation. MATERIALS AND METHODS: We performed a retrospective chart review of all MPI and CCTA studies performed at our institution from January 2006 to May 2008. The primary outcome measure was the incidence of referral to invasive coronary angiography (ICA). RESULTS: There were 512 MPS and 170 CCTA studies performed during the study period that met the study criteria. The average age was 35±10 for the CCTA arm and 45±5 for the myocardial perfusion scans (MPS) arm, which was statistically significant (P<0.001), with similar sex distribution between the 2 arms (21% female patients in the MPI arm and 20% female patients in the CCTA arm). The incidence of referral to ICA was 15.8% (81/512) after MPS versus 2.4% (4/170) with CCTA (P<0.001). Among patients referred for ICA, the false-positive rate was 93% (75/81) and 50% (2/4) with MPI and CCTA, respectively (P=0.043). CONCLUSIONS: Compared with MPI, CCTA significantly reduced ICA referral and false-positive noninvasive imaging rates among symptomatic patients with a low probability of coronary artery disease but high occupational risk.

The effect of airway pressure release ventilation on pulmonary catheter readings: specifically pulmonary capillary wedge pressure in a Swine model.

Background. Airway pressure release ventilation (APRV) is a mode of mechanical ventilation that theoretically believed to improve cardiac output by lowering right atrial pressure. However, hemodynamic parameters have never been formally assessed. Methods. Seven healthy swine were intubated and sedated. A baseline assessment of conventional ventilation (assist control) and positive end-expiratory pressure (PEEP) of 5 cm H(2)O was initiated. Ventilator mode was changed to APRV with incremental elevations of CPAP-high from 10 to 35 cm H(2)O. After a 3-to-5-minute stabilization period, measurements of hemodynamic parameters (PCWP, LAP, and CVP) were recorded at each level of APRV pressure settings. Results. Increasing CPAP caused increased PCWP and LAP measurements above their baseline values. Mean PCWP and LAP were linearly related (LAP = 0.66(∗)PCWP + 4.5 cm H(2)O, R(2) = 0.674, and P < .001) over a wide range of high and low CPAP values during APRV. With return to conventional ventilation, PCWP and LAP returned to their baseline values. Conclusion. PCWP is an accurate measurement of LAP during APRV over variable levels of CPAP. However, PCWP and LAP may not be accurate measurements of volume when CPAP is utilized.

Marathon running as a cause of troponin elevation: a systematic review and meta-analysis.

BACKGROUND: Cardiac troponin (cTn) has high sensitivity and specificity for myocardial injury in acute coronary syndrome. Our objective was to review the published literature regarding the incidence of cTn elevations in marathon runners. METHODS: Systematic review and meta-analysis of observational studies published before September 2009. We included studies of patients who had completed a marathon and had serum cTn levels within 24 hours. The primary outcome was the odds ratio for conversion of a normal pre-marathon cTn to an elevated post-marathon cTn. Secondary outcomes included the pooled prevalence of cTn elevation and comparison of the odds ratio for post-marathon elevation of cTnI versus cTnT. RESULTS: Sixteen studies of 939 participants met criteria for inclusion. The mean age was 39 ± 4 years and patients were 74 ± 14% male. There were 6 pre-marathon cTn elevations and 579 post-race elevations. The pooled odds ratio for converting from a normal pre-race to an elevated post-race cTn was 51.84 (95% CI 16-168, I² = 66%, P < 0.001). The pooled incidence of a post-marathon cTn elevation was 51% (95% CI 33-69, I² = 98%, P < 0.001) of all runners. For the primary outcome there was no significant publication bias. Age and gender were not associated, but publication date and assay sensitivity was associated with cTn elevation. cTnI was less commonly elevated versus cTnT. CONCLUSIONS: The available data demonstrate that cTn levels are frequently elevated after a marathon with unclear cardiovascular significance. This elevation of cTn appears to be consistent among a diverse patient population.

Discovery of a symptomatic left anomalous coronary artery from the opposite sinus and postoperative considerations.

This is the case of an 18 year old active duty soldier with symptoms of exertional chest pressure and syncope who was found to have anomalous origin of the left main coronary artery (LMCA) from the right coronary cusp (RCC) traveling partially between the great vessels before taking a septal approach between the left ventricular outflow tract (LVOT) and the right ventricular outflow tract (RVOT). Anomalous origin of coronary arteries is a rare condition that carries an increased risk of angina, myocardial ischemia, and sudden cardiac death (SCD). Surgical treatment of such anomalies with both high and lower risk features can be challenging, and traditional benefit from surgical correction may not be achieved due to complex anatomy. As evident by our patient, this rare condition even though benign from sudden death standpoint could be debilitating despite best efforts and available resources.