Prevalence of newly diagnosed sarcoidosis in patients with ventricular arrhythmias: a cardiac magnetic resonance and 18F-FDG cardiac PET study.

Cardiac sarcoidosis (CS) is known to be associated with ventricular tachycardia (VT); however, most investigations to date have focused on patients with known extra-cardiac sarcoidosis. The presence of CS is typically evaluated using 18F-fluorodeoxyglucose (18F-FDG) uptake on cardiac positron emission tomography (PET) or late gadolinium enhancement (LGE) on cardiac magnetic resonance (CMR). In this study, we sought to determine the prevalence of primary CS and the relationship between myocardial 18F-FDG uptake and LGE in patients with VT without known sarcoidosis. We retrospectively identified 67 patients without known sarcoidosis or active ischemic heart disease (i.e. significant ischemic disease that had not been previously revascularized) referred for both CMR and PET for evaluation of VT. Standard cine- and LGE- CMR and cardiac PET protocols were used. Myocardial LGE was defined as signal intensity > 5 SDs above the mean signal intensity of normal myocardium. Cardiac PET images were considered positive if there was focal myocardial 18F-FDG uptake having greater activity than the left ventricular blood pool. 45 patients (67%) had LGE, while only 4 (6%) had myocardial FDG uptake. Nine percent of patients with LGE had FDG-uptake while none without LGE did, and 10% of the cohort had indeterminate FDG uptake presumably from poor dietary preparation. Of those with both FDG uptake and LGE, 3/4 ultimately received a clinical diagnosis of CS. 4.5% of patients without previously known sarcoidosis or active ischemic heart disease presenting with VT have newly diagnosed CS. Detection of CS can be increased using a CMR first approach followed by cardiac PET for patients with non-ischemic LGE.

Refining Severe Tricuspid Regurgitation Definition by Echocardiography with a New Outcomes-Based "Massive" Grade.

BACKGROUND: Current echocardiographic guidelines recommend that tricuspid regurgitation (TR) severity be graded in three categories, following assessment of specific parameters. Findings from recent trials have shown that the severity of TR frequently far exceeds the current definition of severe. We postulated that a grading approach that emphasizes outcomes could be useful to identify patients with severe TR at increased risk of mortality. METHODS: We identified 284 patients with echocardiograms demonstrating severe functional TR, defined as vena contracta (VC) ≥ 0.7 cm. Demographics and mortality data were obtained from the medical records. Patients were divided into study (n = 122 patients with three-dimensional images) and validation (n = 162) cohorts. The VC was measured in both the right ventricular (RV) inflow and apical four-chamber views and averaged. For the study cohort, tricuspid annular, RV end-diastolic (basal, mid, long axis) dimensions, tricuspid leaflet tenting height and area, RV free-wall longitudinal strain, and RV volumes were measured from two- and three-dimensional data sets. A K-partition algorithm was used in the study cohort to derive a mortality-related cutoff VC value, above which TR was termed "massive." The ability of this VC cutoff to identify patients at greater mortality risk was then tested in the validation cohort using Kaplan-Meier survival analysis. RESULTS: In the study cohort, VC > 0.92 cm (massive TR) was optimally associated with worse survival. Tricuspid annular and RV size were larger in the massive group (P < .05), while there were no significant differences in demographics between the TR groups. Importantly, in the independent validation cohort, the above VC cutoff also correlated with increased mortality in the massive group (log-rank P < .05). CONCLUSIONS: Among patients traditionally defined as having severe TR, a subset exists with massive TR, resulting in greater adverse RV remodeling and increased mortality. These patients may derive the greatest benefit from emerging percutaneous therapies.

Importance of the Left Atrium: More Than a Bystander?

Left atrial size and function parameters are associated with adverse outcomes in multiple disease states, including heart failure with reduced and preserved ejection fraction. Recent data suggest that phasic left atrial function and left atrial stain measurements also hold prognostic information. Three-dimensional echocardiography provides more accurate and reproducible quantification of left atrial volumes than 2-dimensional echocardiography when compared with cardiac magnetic resonance reference standards. Greater accessibility to these advanced imaging techniques allows for the integration of these parameters into routine clinical practice.

Pregnancy and postpartum infective endocarditis: a systematic review.

The objective of this review was to describe the clinical characteristics, risk factors, and outcomes of infective endocarditis (IE) in pregnancy and the postpartum period. We conducted a systematic review of Ovid MEDLINE, Ovid Embase, Web of Science, and Scopus from January 1, 1988, through October 31, 2012. Included studies reported on women who met the modified Duke criteria for the diagnosis of IE and were pregnant or postpartum. We included 72 studies that described 90 cases of peripartum IE, mostly affecting native valves (92%). Risk factors associated with IE included intravenous drug use (14%), congenital heart disease (12%), and rheumatic heart disease (12%). The most common pathogens were streptococcal (43%) and staphylococcal (26%) species. Septic pulmonary, central, and other systemic emboli were common complications. Of the 51 pregnancies, there were 41 (80%) deliveries with survival to discharge, 7 (14%) fetal deaths, 1 (2%) medical termination of pregnancy, and 2 (4%) with unknown status. Maternal mortality was 11%. Infective endocarditis is a rare, life-threatening infection in pregnancy. Risk factors are changing with a marked decrease in rheumatic heart disease and an increase in intravenous drug use. The cases reported in the literature were commonly due to streptococcal organisms, involved the right-sided valves, and were associated with intravenous drug use.

Evaluation of apical subtype of hypertrophic cardiomyopathy using cardiac magnetic resonance imaging with gadolinium enhancement.

Apical hypertrophic cardiomyopathy (HC) is an uncommon variant of HC. We sought to characterize cardiac magnetic resonance imaging (MRI) findings among apical HC patients. This was a retrospective review of consecutive patients with a diagnosis of apical HC who underwent cardiac MRI examinations at the Mayo Clinic (Rochester, MN) from August 1999 to October 2011. Clinical and demographic data at the time of cardiac MRI study were abstracted. Cardiac MRI study and 2-dimensional echocardiograms performed within 6 months of the cardiac MRI were reviewed; 96 patients with apical HC underwent cardiac MRI examinations. LV end-diastolic and end-systolic volumes were 130.7 ± 39.1 ml and 44.2 ± 20.9 ml, respectively. Maximum LV thickness was 19 ± 5 mm. Hypertrophy extended beyond the apex into other segments in 57 (59.4%) patients. Obstructive physiology was seen in 12 (12.5%) and was more common in the mixed apical phenotype than the pure apical (19.3 vs 2.6%, p = 0.02). Apical pouches were noted in 39 (40.6%) patients. Late gadolinium enhancement (LGE) was present in 70 (74.5%) patients. LGE was associated with severe symptoms and increased maximal LV wall thickness. In conclusion, cardiac MRI is well suited for studying the apical form of HC because of difficulty imaging the cardiac apex with standard echocardiography. Cardiac MRI is uniquely suited to delineate the presence or absence of an apical pouch and abnormal myocardial LGE that may have implications in the natural history of apical HM. In particular, the presence of abnormal LGE is associated with clinical symptoms and increased wall thickness.

Evaluation of apical pouches in hypertrophic cardiomyopathy using cardiac MRI.

The presence of apical pouches in hypertrophic cardiomyopathy (HCM) may portend poor prognosis. We sought to study if the use cardiac magnetic resonance imaging (CMR) improves the detection of apical pouches in HCM compared to echocardiography. A retrospective review was performed of all consecutive HCM patients with an apical pouch identified by CMR at Mayo Clinic from May 2004 to Sept 2011. Clinical data was abstracted and CMR and echocardiographic images were analyzed. There were 56 consecutive HCM patients with an apical pouch identified by CMR. The predominant morphological type was apical in 41 (73.2 %), followed by sigmoid in 6 (10.7 %), reversed curve in 6 (10.7 %) and neutral in 3 (5.4 %). Obstructive physiology or systolic anterior motion of the mitral valve leaflet was evident in 23 (41.1 %). Late gadolinium enhancement was present in 47 (87.0 %) patients. Apical pouches were detected in only 18 (32.1 %) patients on echocardiography. Even when intravenous contrast was used (29/56 patients), in 16/29 (55.2 %) pouches were missed on echocardiography. Pouch length and neck dimensions in systole and diastole, measured on CMR, were larger among those patients in whom pouches were detected on echocardiography suggesting only larger pouches can be identified on echocardiography. In the largest CMR series to date of apical pouches in HCM, we show that while apical pouches are most commonly seen in apical HCM, they can be found in other phenotypic variants. CMR is better suited for the evaluation of apical pouches compared to echocardiography even with the use of intravenous contrast. CMR is likely a better tool for evaluating the cardiac apical structures including apical pouches when clinically indicated.

Therapeutic hypothermia after out-of-hospital cardiac arrest: evaluation of a regional system to increase access to cooling.

BACKGROUND: Therapeutic hypothermia (TH) improves survival and confers neuroprotection in out-of-hospital cardiac arrest (OHCA), but TH is underutilized, and regional systems of care for OHCA that include TH are needed. METHODS AND RESULTS: The Cool It protocol has established TH as the standard of care for OHCA across a regional network of hospitals transferring patients to a central TH-capable hospital. Between February 2006 and August 2009, 140 OHCA patients who remained unresponsive after return of spontaneous circulation were cooled and rewarmed with the use of an automated, noninvasive cooling device. Three quarters of the patients (n=107) were transferred to the TH-capable hospital from referring network hospitals. Positive neurological outcome was defined as Cerebral Performance Category 1 or 2 at discharge. Patients with non-ventricular fibrillation arrest or cardiogenic shock were included, and patients with concurrent ST-segment elevation myocardial infarction (n=68) received cardiac intervention and cooling simultaneously. Overall survival to hospital discharge was 56%, and 92% of survivors were discharged with a positive neurological outcome. Survival was similar in transferred and nontransferred patients. Non-ventricular fibrillation arrest and presence of cardiogenic shock were associated strongly with mortality, but survivors with these event characteristics had high rates of positive neurological recovery (100% and 89%, respectively). A 20% increase in the risk of death (95% confidence interval, 4% to 39%) was observed for every hour of delay to initiation of cooling. CONCLUSIONS: A comprehensive TH protocol can be integrated into a regional ST-segment elevation myocardial infarction network and achieves broad dispersion of this essential therapy for OHCA.