Myocardial Flow Reserve and Coronary Calcification in Prognosis of Patients With Suspected Coronary Artery Disease.

OBJECTIVES: The aim of this analysis is to examine the incremental prognostic value of coronary artery calcium (CAC) score and myocardial flow reserve (MFR) in patients with suspected coronary artery disease (CAD) undergoing positron emission tomography (PET) myocardial perfusion imaging (MPI). BACKGROUND: Advances in cardiac PET and computed tomography imaging enabled the simultaneous acquisition of anatomic and physiological data for patients suspected of CAD. METHODS: Consecutive patients who underwent PET MPI and CAC score calculation at King Abdulaziz Cardiac Center, Riyadh, Saudi Arabia, between May 2011 and May 2018 were included in the study. MPI and CAC images were obtained in the same setting. The primary endpoint of the study was a composite of cardiac death and nonfatal myocardial infarction. Cox proportional hazard regression was used to assess the incremental prognostic value of CAC and MFR by sequentially adding the variables to a model that included clinical and PET variables. RESULTS: A total of 4,008 patients (mean age 59.7 ± 11.6 years, 55% women) were included in the analysis. Risk factors were prevalent (77.6% hypertension, 58.1% diabetes). In total, 35.9% of the cohort had CAC of 0, 16.5% had CAC ≥400, and 43.9% had MFR <2. Over a median follow up of 1.9 years, 130 (3.2%) patients had cardiac death/nonfatal myocardial infarction. CAC and MFR score added incremental prognostic value over clinical and perfusion variables (base model: c-index 0.8137; Akaike information criterion [AIC]: 1,865.877; p = 0.0011; CAC model: c-index = 0.8330; AIC: 1,850.810; p = 0.045 vs. base model; MFR model: c-index = 0.8279; AIC: 1,859.235; p = 0.024). Combining CAC and MFR did not enhance risk prediction (c-index = 0.8435; AIC: 1,846.334; p = 0.074 vs. MFR model; p = 0.21 vs. CAC model.) CONCLUSIONS: In this large cohort of patients referred for PET MPI, both CAC and MFR independently added incremental prognostic value over clinical and MPI variables. Although combining both may have synergetic prognostic effect, this relation was not shown in multivariable model of this analysis.

Mitral annular geometry in normal and myxomatous mitral valves: three-dimensional transesophageal echocardiographic quantification.

BACKGROUND AND AIM OF THE STUDY: The mitral annulus (MA) has a complex dynamic geometry that is difficult to visualize in two dimensions; hence, novel real-time three-dimensional transesophageal echocardiography (RT-3D-TEE) provides insights into its dynamic nature. The study aim was to investigate changes in MA geometry in normal subjects and to explore differences in patients with myxomatous mitral valve disease (MMVD), using 3D quantitation with RT-3D-TEE. METHODS: Thirty-five participants (18 with MMVD, 17 normal subjects as controls) were enrolled into the study. The following geometric measurements were obtained at end-systole (ES) and end-diastole (ED): surface area, circumference, perimeter, height, commissure-to-commissure (C-C) diameter, anterior-to-posterior (A-P) diameter, and the ratio of A-P diameter to C-C diameter (circularization). To detect the effect of the severity of mitral regurgitation (MR) on MA dynamics, patients with MMVD were allocated to two subgroups with mild (n = 7) or moderate/severe (n = 11) MR. RESULTS: Control subjects demonstrated a saddle-shaped, elliptical MA configuration with slightly larger ES parameters. The MA shape was changed during the cardiac cycle, being more circular at ES and flatter at ED (p < 0.05). In MMVD patients, the MA retained a saddle shape but became dilated and circular with larger ED parameters compared to controls (p < 0.05). The degree of MA geometric changes was more prominent in moderate/severe MR patients (p < 0.001), while mild MR patients displayed MA geometry and dynamics similar to those of controls. CONCLUSION: The MA geometry is altered in MMVD patients, with the extent of changes being determined by the severity of the MR. RT-3D-TEE provides high-quality images that permit a precise quantitative analysis of the 3D geometry of the MA.

The left ventricle responds to acute graded elevation of right ventricular afterload by augmentation of twist magnitude and untwist rate.

BACKGROUND: The right and left ventricles share the interventricular septum, which mechanically transmits pressure gradients. The aim of this study was to investigate how acute mild or moderate right ventricular (RV) afterload affects left ventricular (LV) function. METHODS: In 14 open-chest pigs (mean weight, 43 ± 4 kg) with preserved pericardium, acute mild (>35 and ≤50 mm Hg) and moderate (>50 and ≤60 mm Hg) RV pressure loading conditions were induced by constriction of the pulmonary artery. Hemodynamic parameters and LV twist and untwist were evaluated under each condition. RESULTS: From baseline to mild and moderate RV afterload, the mean RV systolic pressure increased from 31.0 ± 4.3 to 41.1 ± 2.7 and 52.7 ± 3.4 mm Hg (P < .001), while LV twist magnitudes increased from 15.4 ± 5.1° to 18.5 ± 3.1° and 19.8 ± 5.0° (P = .004), respectively. Absolute values of LV untwist rate increased from -116.9 ± 64.9°/sec to -160.0 ± 53.3°/sec and -169.1 ± 47.0°/sec, respectively (P = .001). After adjusting for all variables, only the ratio of the early and atrial components of mitral inflow and RV outflow tract acceleration time was significantly associated with the LV twist magnitude and LV untwist rate. CONCLUSIONS: In an acute setting, the left ventricle responds to suddenly elevated RV afterload and decreased RV stroke volume by promptly increasing its twist magnitude and untwist rate.

Global left atrial dysfunction and regional heterogeneity in primary chronic mitral insufficiency.

AIMS: We assessed the hypothesis that global and regional left atrial (LA) function is altered in patients with chronic primary mitral regurgitation (MR) secondary to myxomatous mitral valve disease (MMVD). METHODS AND RESULTS: Velocity vector imaging of the LA was acquired from apical four- and two-chamber views in 41 normal and 43 subjects with chronic MR due to MMVD. All had normal left ventricular systolic function. The LA subendocardium was traced to obtain atrial volumes, ejection fraction, velocities, and strain (ε)/strain rate (SR) measurements. To explore the effects of MR severity on LA function, subjects were divided into two groups: mild vs. moderate/severe MR. Reservoir (expansion and diastolic emptying indices), booster pump (active emptying index) functions, and LA ejection fraction were markedly impaired in subjects with MR (P < 0.001). Mean LA ε was reduced in moderate/severe MR compared with control subjects (P < 0.01). A consistent pattern of differences in atrial regional function was noted with the anterior wall having a lower peak systolic ε/SR, which is more evident in the moderate/severe MR group (P < 0.01) when compared with controls and mild MR groups. CONCLUSION: LA filling during ventricular systole (reservoir function), LA contraction (booster pump function), and ejection fraction were significantly impaired in patients with chronic MR. Regional differences in LA contractility at the anterior wall were noted presumably due to the eccentricity of the systolic anteriorly directed MR jet hitting the anterior wall and altering local wall mechanics.

Prediction of incipient left ventricular dysfunction in patients with chronic primary mitral regurgitation: a velocity vector imaging study.

AIMS: Progressive left ventricular (LV) dilatation and irreversible myocardial damage are important causes of morbidity and mortality in patients with chronic primary mitral regurgitation (MR) due to myxomatous mitral valve disease. We assessed the hypothesis that early subclinical LV dysfunction secondary to chronic primary MR could be signalled by abnormal LV rotation mechanics, utilizing velocity vector imaging (VVI). METHODS AND RESULTS: Forty-three with chronic primary MR and 41 normal subjects were evaluated. All had normal LV systolic function. Peak endocardial and epicardial rotations in systole were measured in apical and basal short-axis images. LV twist was defined as the net difference between apical and basal angles of rotation while LV torsion was calculated as LV twist divided by LV diastolic longitudinal length. To explore the effects of MR severity on LV rotation, patients were divided into three groups: mild, moderate, and severe MR. The peak twist and torsion of the LV endocardium displayed significant differences across the study groups (P = 0.005 and 0.015, respectively). Subjects with moderate MR revealed the highest LV rotation profile (2.26 ± 0.66°/cm and 17.83 ± 5.2° for torsion and twist, respectively), implicating hyperdynamic LV function. However, severe MR group showed the lowest LV rotation profile (1.39 ± 0.8°/cm and 11.43 ± 6.09° for torsion and twist, respectively), suggesting incipient LV dysfunction. There were no significant differences in epicardial LV rotations. CONCLUSION: Evaluation of global LV function by VVI is a novel reproducible index for detecting subnormal latent LV dysfunction in chronic MR patients, which may aid in the optimal timing of surgery.

Risk of adverse events after coronary artery bypass graft and subsequent noncardiac surgery.

AIMS: Coronary artery bypass grafts (CABGs) are increasingly performed in elderly patients. Risk factors and outcomes are poorly described for those undergoing noncardiac surgery within 1 year after CABG. Our objectives were to assess the risk and predictors of major adverse events associated with noncardiac surgery within 1 year after CABG. METHODS: In a retrospective review of medical records at Mayo Clinic (Rochester, MN, USA), over a period of 5 years, we identified patients who underwent noncardiac procedures within 1 year post-CABG. All events that occurred within 30 days after noncardiac surgery and deaths within 1 year after noncardiac surgery were considered to be related to CABG. RESULTS: We identified 211 patients; of these, 21 patients had 24 adverse events. Within 1 year, 11 died, and within the first 30 days, three myocardial infarctions, six acute congestive heart failure episodes, three cerebrovascular accidents and one deep vein thrombosis episode had occurred. Predictors of an adverse event included emergency operation (odds ratio: 6.8), ejection fraction less than 45% (p < 0.001) and elevated right ventricular systolic pressure by 40 mmHg or more (p = 0.03). After the noncardiac procedure, patients requiring dialysis (p = 0.02), ventilatory support (p = 0.03) and longer hospital stay (p = 0.03) had greater rates of adverse outcomes. CONCLUSION: Post-CABG, preoperative ejection fraction less than 45%, right ventricular systolic pressure of 40 mmHg or more, as well as emergent noncardiac surgery, were predictors of adverse outcomes after the noncardiac procedure. Longer postoperative hospital stay, dialysis, as well as ventilatory support, were predictors of adverse outcomes after CABG.

Coronary computed tomography angiography in a patient with atrial fibrillation, case report.

Atrial fibrillation (AF) is the most common persistent arrhythmia. It is associated with wide range of cardiac clinical conditions. Because of variable duration of cardiac cycle resulting in reduced image quality, AF has been considered relative contraindication for performing coronary computed tomography angiography (CCTA). However, recent reports have suggested that newer dual source scanner with higher temporal resolution can be used in patients with AF (Oncel et al., 2007; Wolak et al., 2008; Rist et al., 2009). Image quality can be maintained if heart rate is lowered to less than 70 beats per minute. However, high heart rate can still be challenging. Mapping systolic phase with the use of absolute delay reconstruction algorithm has been shown to provide better image quality. In this article, we present a case of patient with chronic AF and in whom coronary examination was required before going to repair of aortic root dissection. CCTA, with the use of absolute delay reconstruction algorithm, provided diagnostic image quality of the coronary arteries.

Impact of pericardial adhesions on diastolic function as assessed by vortex formation time, a parameter of transmitral flow efficiency.

BACKGROUND: Pericardial adhesions are a pathophysiological marker of constrictive pericarditis (CP), which impairs cardiac filling by limiting the total cardiac volume compliance and diastolic filling function. We studied diastolic transmitral flow efficiency as a new parameter of filling function in a pericardial adhesion animal model. We hypothesized that vortex formation time (VFT), an index of optimal efficient diastolic transmitral flow, is altered by patchy pericardial-epicardial adhesions. METHODS: In 8 open-chest pigs, the heart was exposed while preserving the pericardium. We experimentally simulated early pericardial constriction and patchy adhesions by instilling instant glue into the pericardial space and using pericardial-epicardial stitches. We studied left ventricular (LV) function and characterized intraventricular blood flow with conventional and Doppler echocardiography at baseline and following the experimental intervention. RESULTS: Significant decreases in end-diastolic volume, ejection fraction, stroke volume, and late diastolic filling velocity reflected the effects of the pericardial adhesions. The mean VFT value decreased from 3.61 ± 0.47 to 2.26 ± 0.45 (P = 0.0002). Hemodynamic variables indicated the inhibiting effect of pericardial adhesion on both contraction (decrease in systolic blood pressure and +dP/dt decreased) and relaxation (decrease in the magnitude of -dP/dt and prolongation of Tau) function. CONCLUSION: Patchy pericardial adhesions not only negatively impact LV mechanical functioning but the decrease of VFT from normal to suboptimal value suggests impairment of transmitral flow efficiency.

Parachute mitral valve in adults-a systematic overview.

Parachute mitral valve (PMV) is a rare congenital anomaly of the mitral valve apparatus seen in infants and young children. In most instances PMV is associated with other congenital anomalies of the heart, in particular obstructive lesions of the mitral inflow (mitral valve ring) and left ventricular outflow tract (subaortic stenosis), and coarctation of aorta and is referred to as Shone's complex or Shone's anomaly. PMV may also occur as an isolated lesion or in association with other congenital cardiac anomalies. Not much is known about PMV in adults as an isolated anomaly or in association with other congenital cardiac anomalies. We reviewed the literature to identify cases of PMV (isolated or associated with other lesions) in adults, to address prevalence, clinical presentation, diagnosis, treatment, and outcome of such patients. (Echocardiography 2010;27:581-586).

Rheumatic tricuspid valve disease: an evidence-based systematic overview.

BACKGROUND AND AIM OF THE STUDY: Right-sided valve abnormalities are less common than their left-sided counterparts. Furthermore, whilst organic rheumatic involvement of the tricuspid valve is not uncommon, it receives less attention than left-sided heart valves. An evidence-based systematic overview was carried out to assess the epidemiology, diagnosis and management of organic rheumatic tricuspid valve disease (RTVD) over the past half century. METHODS: A computed search spanning more than four decades was conducted to identify articles on various aspects of RTVD. The bibliographies of all relevant articles were also searched. RESULTS: A total of 2,497 rheumatic heart disease patients (mean age 25.5 years; female:male ratio 1.3:1) was included. RTVD was detected in 193 patients (7.7%). Echocardiography was used to detect tricuspid valve involvement in all patients. Associated mitral valve disease was present in 99.3% of the patients with RTVD. A total of 1,092 patients (mean age 45.4 years) was included from six studies on surgical correction of the tricuspid valve. Of these patients, 278 (25.4%) underwent tricuspid valve replacement, while 814 (74.5%) had tricuspid valve repair. The in-hospital mortality was 9.9%, and late mortality 33.2% CONCLUSION: RTVD is not uncommon among patients with rheumatic heart disease, but attracts less attention and might, therefore, be overlooked. Echocardiography is the most common diagnostic tool. Although indications for surgical intervention are not well defined, valve repair may have a better outcome than replacement.

Fatal migratory pulmonary thromboembolism following successful pericardiocentesis.

Echocardiography-guided pericardiocentesis is relatively safe with minimal risk in experienced hands. However, complications can occur because of the procedure. This report describes a unique case of an 84-year-old man with unanticipated fatal pulmonary thromboembolism following a successful pericardiocentesis.

Multimodality imaging showing complete cardiovascular involvement by Erdheim-Chester disease.

Erdheim-Chester disease (ECD) is a multisystem non-Langerhans form of cell histiocytosis. Histiocytic infiltration leads to xanthogranulomatous infiltrates of multiple organ systems. Erdheim-Chester disease was first reported in 1930, only 320 cases reported in the literature. Cardiac involvement in ECD carries worst prognosis beside the central nervous system. We report the first case with pan-cardiac involvement diagnosed with multimodality imaging.

Evaluation of left ventricular rotation in obese subjects by velocity vector imaging.

AIMS: Obesity is a well-known risk factor in the development of cardiovascular disease. We hypothesize that early left ventricular (LV) dysfunction secondary to obesity could be signalled by abnormal LV rotation. METHODS AND RESULTS: This prospective study examined 60 subjects divided into two groups: obese group with body mass index (BMI) >or=30 and control group with BMI <25. The peak rotation, twist, and torsion of the left ventricle were studied in obese and control subjects, using velocity vector imaging. Age and gender were comparable between the two groups. Obese subjects had higher BMI, waist circumference, fasting glucose, triglycerides, systolic and diastolic blood pressure, low-density lipoprotein cholesterol, and lower high-density lipoprotein cholesterol (P < 0.05). In obese subjects, LV mass and LV mass index were increased, and the ratio of mitral early and late diastolic filling velocity was decreased (P < 0.05). In obese subjects, the peak twist and torsion of the left ventricle displayed a lower trend, and the peak rotation of the left ventricle apex decreased significantly (3.81 +/- 2.09 degrees vs. 5.77 +/- 3.27 degrees , P < 0.001). CONCLUSION: Obesity was associated with changes in LV rotation. Velocity vector imaging is a feasible and reproducible echocardiographic technique for the detection of early subclinical LV dysfunction.

Unicuspid aortic valve in adults: a systematic review.

BACKGROUND AND AIM OF THE STUDY: The natural history of the unicuspid aortic valve (UAV) is poorly described in the literature. In order to study the association between UAV with any other cardiac or extra cardiac abnormalities, an evidence-based systematic review was carried out. METHODS: A computerized search was carried out of the medical literature published between 1st January 1966 and 1st September 2008 of the following databases: MEDLINE; EMBASE; Web of Science; and the Cochrane Database. RESULTS: A total of 231 cases of adult UAV was identified in 38 articles. The mean patient age was 42 years, and the most common presenting symptoms reported (in 52 cases) included dyspnea (44%; n=23), angina (21%; n=11), and dizziness or syncope (8%; n=4). The most common lesion in UAV was isolated aortic stenosis (AS) (41%; n=95) and AS with or without aortic regurgitation (28%; n=64). The preoperative diagnosis of UAV is rare, and 139 cases (60%) of UAV were reported at autopsy or by examination of surgically excised valves. Aortic valve replacement was performed in 166 cases (82%). Concomitant aortic surgery was performed in 47 of the UAV cases (23%), either for a dilated or aneurysmal aorta. CONCLUSION: UAV shares many of the features of bicuspid aortic valve, including valvular dysfunction, aortic dilatation, aortic dissection, and dystrophic calcification, although these conditions develop at an earlier age and progress at a faster pace in UAV. Further investigations are warranted regarding the possibility of a familial incidence, associated histopathological changes in the aorta, preoperative diagnostic tools, ideal follow up and surgical intervention.

Epicardial fat and its association with cardiovascular risk: a cross-sectional observational study.

BACKGROUND: The association between visceral obesity and cardiovascular risk has been well described. Some studies show a proportional relationship between the presence of visceral obesity and epicardial fat. Measuring the amount of epicardial adipose tissue (EAT) can be a novel parameter that is inexpensive and easy to obtain and may be helpful in cardiovascular risk stratification. However, the relationship between epicardial fat and cardiac function and that between epicardial fat and cardiac risk factors is less well described. OBJECTIVES: To evaluate the association between echocardiographic epicardial fat and the morphologic and physiologic changes observed at echocardiography and to evaluate the association between epicardial fat and cardiac risk factors. A cross-sectional study of 97 echocardiographic studies (females, n = 42) was conducted. Two groups were identified: epicardial fat ≥ 5 mm (group I) and <5 mm (group II). RESULTS: Epicardial fat >5 mm was associated with LA enlargement, with lower ejection fraction, increased left ventricular mass, and abnormal diastolic function. On a multivariable regression analysis, all these parameters also correlated individually with EAT thickness independent of age. Hyperglycemia (DM), systolic hypertension, and lipid parameters for metabolic syndrome showed a trend for positive association, but this was not statistically significant. The association was not significant even for higher cutoff limits of EAT thickness. CONCLUSION: Epicardial fat >5 mm is associated with cardiac abnormalities on echocardiography. This is a sensitive assessment of body fat distribution, is easily available at echocardiography, and is simple to acquire at no added cost. Further studies looking at the appropriate cut-off thickness of EAT and the sites of measurement to be used are needed. Comparison of this simple and inexpensive measure with other measures of obesity, such as waist-hip ratio, body mass index, Dexa scan of visceral fat, and magnetic resonance imaging of visceral, are needed.

Quantification of left ventricular twisting mechanics by velocity vector imaging in an animal model of pericardial adhesions.

Diagnosis of constrictive pericarditis remains clinically challenging. Untwisting of the left ventricle (LV) is essential for normal LV diastolic function. Echocardiography is able to measure LV twisting mechanics. We designed an animal model of constrictive pericarditis to determine how pericardial-epicardial adhesions impair LV twisting mechanics. In eight open-chest pigs, the heart was exposed while preserving the pericardium. We simulated early constrictive pericarditis by pericardial constriction and patchy adhesions induced with instant glue and pericardial-epicardial stitches. Using Velocity Vector Imaging (VVI), LV magnitudes of twisting and untwisting were measured along with hemodynamic data at baseline and after the experimental intervention. Significant decreases in end-diastolic volume, ejection fraction, stroke volume, and late diastolic filling velocity reflected the effects of the pericardial adhesions. Magnitude of LV untwisting rate decreased from -80+/-23 degrees /s to -26+/-10 degrees /s (p=0.0009). LV twisting rate dropped from 78+/-20 degrees /s to 40+/-8 degrees /s (p=0.0039) and LV twist magnitude decreased from 9+/-2 degrees to 5+/-2 degrees (p=0.0081). Patchy pericardial adhesions are associated with reductions in LV untwisting rate and twisting magnitude, consistent with a negative impact of constrictive pericarditis on systolic and diastolic function. Impairments in LV twisting mechanics may have a diagnostic role in the detection of early stages of constrictive pericarditis.

Correlation of automated function imaging (AFI) to conventional strain analyses of regional and global right ventricular function.

BACKGROUND: Automated function imaging is a software tool available to facilitate the efficiency of workflow when analyzing left ventricular strain. In this study, automated function imaging was compared with a conventional approach for the analysis of right ventricular strain in normal and pressure-overloaded right ventricles. METHODS: Twelve pigs were subjected to graded acute right ventricular systolic pressure overload. Intraclass and interclass correlation coefficients (ICCs) with 95% confidence intervals were used for statistical evaluation, with grading based on the kappa statistic as follows: ICC >0.75 = excellent, 0.4 to 0.75 = good, and <0.40 = poor. RESULTS: Intraobserver and interobserver variability for both regional and global strains consistently ranged from good to excellent (ICC, 0.50-0.99), with good agreement between the conventional and automated methods. CONCLUSION: Automated function imaging correlates well with conventional strain analysis of the right ventricle. Automated function imaging is a practical tool for measuring regional and global longitudinal strain in both normal and pressure-overloaded right ventricles.

Extensive cardiac metastases secondary to uterine leiomyosarcoma.

Uterine leiomyosarcoma metastatic to multiple cardiac chambers occurs infrequently. Over the past 4 decades, there have been only 11 reported cases of cardiac metastasis secondary to uterine leiomyosarcoma. Metastatic cardiac tumors are commonly diagnosed postmortem, although it may be possible to diagnose them during life. The authors report a rare case of a 48-year-old woman with uterine leiomyosarcoma who was diagnosed with extensive cardiac metastases (in the left atrium, right and left ventricles, pulmonary artery, and pulmonary vein). Although extensive cardiac metastases are suggestive of imminent death, aggressive treatment resulted in survival for >1 year for this patient, which underscores the importance of treatment in select patients.