Quantitative T1 Mapping for Detecting MicrovascularObstruction in Reperfused Acute Myocardial Infarction:Comparison with Late Gadolinium Enhancement Imaging

Objective@#To compare native and post-contrast T1 mapping with late gadolinium enhancement (LGE) imaging for detectingand measuring the microvascular obstruction (MVO) area in reperfused acute myocardial infarction (MI). @*Materials and Methods@#This study included 20 patients with acute MI who had undergone 1.5T cardiovascular magneticresonance imaging (CMR) after reperfusion therapy. CMR included cine imaging, LGE, and T1 mapping (modified look-lockerinversion recovery). MI size was calculated from LGE by full-width at half-maximum technique. MVO was defined as an areawith low signal intensity (LGE) or as a region of visually distinguishable T1 values (T1 maps) within infarcted myocardium.Regional T1 values were measured in MVO, infarcted, and remote myocardium on T1 maps. MVO area was measured on andcompared among LGE, native, and post-contrast T1 maps. @*Results@#The mean MI size was 27.1 ± 9.7% of the left ventricular mass. Of the 20 identified MVOs, 18 (90%) were detectedon native T1 maps, while 10 (50%) were recognized on post-contrast T1 maps. The mean native T1 values of MVO, infarcted,and remote myocardium were 1013.5 ± 58.5, 1240.9 ± 55.8 (p < 0.001), and 1062.2 ± 55.8 ms (p = 0.169), respectively, whilethe mean post-contrast T1 values were 466.7 ± 26.8, 399.1 ± 21.3, and 585.2 ± 21.3 ms, respectively (p < 0.001). The meanMVO areas on LGE, native, and post-contrast T1 maps were 134.1 ± 81.2, 133.7 ± 80.4, and 117.1 ± 53.3 mm2, respectively.The median (interquartile range) MVO areas on LGE, native, and post-contrast T1 maps were 128.0 (58.1–215.4), 110.5(67.7–227.9), and 143.0 (76.7–155.3) mm2, respectively (p = 0.002). Concordance correlation coefficients for the MVO areabetween LGE and native T1 maps, LGE and post-contrast T1 maps, and native and post-contrast T1 maps were 0.770, 0.375,and 0.565, respectively. @*Conclusion@#MVO areas were accurately delineated on native T1 maps and showed high concordance with the areas measuredon LGE. However, post-contrast T1 maps had low detection rates and underestimated MVO areas. Collectively, native T1 mappingis a useful tool for detecting MVO within the infarcted myocardium.

Frequent Premature Atrial Contractions as a Poor Prognostic Factor in Cryptogenic Stroke Patients with Concomitant Non-Sustained Atrial Tachycardia

In cryptogenic stroke patients, early detection of new-onset atrial fibrillation (AF) and recurrent stroke is required to prevent poor clinical outcomes. Therefore, we investigated the predictors of new-onset AF and recurrent stroke in cryptogenic stroke patients without previously diagnosed AF. In total, 390 patients who were diagnosed with stroke and non-sustained atrial tachycardia (NSAT) on 24-hour Holter monitoring were followed up to assess new-onset AF and recurrent stroke. The 5-year event-free survival as well as the predictors of recurrent stroke or new-onset AF were investigated. Based on receiver operating characteristic analysis, frequent premature atrial contractions (PACs) were defined as PACs >44 beats/day. The median follow-up period was 35 months. The composite event rate was 11.5%. In Kaplan-Meier analysis, the 5-year cumulative incidence of composite events was higher in cryptogenic stroke patients with frequent PACs than in those without frequent PACs. Multivariate analysis revealed that current smoking, increased left atrial volume index, and frequent PACs were poor prognostic predictors of composite event, and frequent PACs were an independent poor prognostic factor of new-onset AF in cryptogenic stroke patients. Therefore, frequent PACs might be associated with poor clinical outcomes (new-onset AF and recurrent stroke) in cryptogenic stroke patients with concomitant NSAT.

Pheochromocytoma-induced cardiogenic shock successfully treated by extracorporeal circulation / 영남의대학술지

Pheochromocytoma can present with various symptoms including cardiogenic shock and cardiac arrest. Particularly, in cases of cardiogenic shock of unknown origin, pheochromocytoma should be considered. A 20-year-old woman without any medical history visited our emergency department due to nausea, vomiting, headache, and chest pain. Echocardiography revealed severe left ventricular dysfunction. Mechanical ventilation and veno-arterial extracorporeal membrane oxygenation (ECMO) were implemented owing to her unstable vital signs. For unstable vital sign and cardiogenic shock in a young woman without any previous medical history, pheochromocytoma was considered and diagnosed based on elevated levels of catecholamine derivatives in a 24-hour urine sample. Cardiac function recovered and ECMO was discontinued on the 5th day of hospitalization. She later underwent an elective adrenalectomy and no recurrence was found during the follow-up period. We reported a case of pheochromocytoma which was presented with cardiogenic shock in a young woman with no concomitant disease, and successfully treated with ECMO followed by an elective adrenalectomy.

Pheochromocytoma-induced cardiogenic shock successfully treated by extracorporeal circulation / 영남의대학술지

Pheochromocytoma can present with various symptoms including cardiogenic shock and cardiac arrest. Particularly, in cases of cardiogenic shock of unknown origin, pheochromocytoma should be considered. A 20-year-old woman without any medical history visited our emergency department due to nausea, vomiting, headache, and chest pain. Echocardiography revealed severe left ventricular dysfunction. Mechanical ventilation and veno-arterial extracorporeal membrane oxygenation (ECMO) were implemented owing to her unstable vital signs. For unstable vital sign and cardiogenic shock in a young woman without any previous medical history, pheochromocytoma was considered and diagnosed based on elevated levels of catecholamine derivatives in a 24-hour urine sample. Cardiac function recovered and ECMO was discontinued on the 5th day of hospitalization. She later underwent an elective adrenalectomy and no recurrence was found during the follow-up period. We reported a case of pheochromocytoma which was presented with cardiogenic shock in a young woman with no concomitant disease, and successfully treated with ECMO followed by an elective adrenalectomy.

Associates and Prognosis of Giant Left Atrium; Single Center Experience

BACKGROUND: Left atrial (LA) remodeling develops as a result of longstanding pressure overload. However, determinants and clinical outcome of excessive remodeling, so called giant left atrium (GLA), are not clear. METHODS: Clinical characteristics of patients with GLA (antero-posterior diameter higher than 65 mm), including echo-Doppler parameters, and follow-up clinical outcomes from a tertiary referral hospital were investigated. RESULTS: Among 68519 consecutive primary patients who underwent echocardiography over a period of 10 years, data from 163 GLA cases (0.24%) were analyzed. Main causes were significant rheumatic mitral stenosis (n = 58, 36%); other causes comprised significant rheumatic mitral regurgitation (MR; n = 10, 6%), mitral valve (MV) prolapse or congenital mitral valvular disease (MVD) (n = 20, 12%), and functional MR (n = 25, 15%). However, mild rheumatic MV disease (n = 4, 3%) or left ventricular (LV) systolic or diastolic dysfunction without significant MR (n = 46, 28%) were also causes of GLA. During median follow-up of 22 months, 42 cases (26%) underwent composite events. MV surgery was related to lower rate of composite events. In multivariate analysis, MV surgery, elevated pulmonary arterial systolic pressure, and increased LA volume index were independent predictors of future events (p < 0.05) regardless of underlying diseases or history of MV surgery. CONCLUSION: Although rheumatic MVD with atrial fibrillation is the main contributor to GLA, longstanding atrial fibrillation with LV dysfunction but without MVD also could be related to GLA. Even in GLA state, accurate measurement of LA volume is crucial for risk stratification for future events, regardless of underlying disease.

Current Awareness and Use of the Strain Echocardiography in Routine Clinical Practices: Result of a Nationwide Survey in Korea

BACKGROUND: Because conventional echocardiographic parameters have several limitations, strain echocardiography has often been introduced in clinical practice. However, there are also obstacles in using it in clinical practice. Therefore, we wanted to find the current status of awareness on using strain echocardiography in Korea. METHODS: We conducted a nationwide survey to evaluate current use and awareness of strain echocardiography from the members of the Korean Society of Echocardiography. RESULTS: We gathered total 321 questionnaires from 25 cardiology centers in Korea. All participants were able to perform or interpret echocardiographic examinations. All participating institutions performed strain echocardiography. Most of our study participants (97%) were aware of speckle tracking echocardiography and 185 (58%) performed it for clinical and research purposes. Two-dimensional strain echocardiography was the most commonly used modality and left ventricle (LV) was the most commonly used cardiac chamber (99%) for clinical purposes. Most of the participants (89%) did not think LV strain can replace LV ejection fraction (LVEF) in their clinical practice. The common reasons for not performing routine use of strain echocardiography was diversity of strain measurements and lack of normal reference value. Many participants had a favorable view of the future of strain echocardiography. CONCLUSION: Most of our study participants were aware of strain echocardiography, and all institutions performed strain echocardiography for clinical and research purposes. However, they did not think the LV strain values could replace LVEF. The diversity of strain measurements and lack of normal reference values were common reasons for not using strain echocardiography in clinical practice.

Prognostic Value of Elevated Homocysteine Levels in Korean Patients with Coronary Artery Disease: A Propensity Score Matched Analysis

BACKGROUND AND OBJECTIVES: We sought to determine whether an elevated homocysteine (Hcy) level is associated with a worse prognosis in Korean patients with coronary artery disease (CAD). SUBJECTS AND METHODS: A total of 5839 patients (60.4% male, mean age 61.3±11.2 years) with CAD were enrolled from 2000 to 2010 at Gangnam Severance Hospital. CAD was diagnosed by invasive coronary angiography. Laboratory values including Hcy level were obtained on the day of coronary angiography and analyses were performed shortly after sampling. Patients were divided into two groups according to their Hcy levels. Baseline risk factors, coronary angiographic findings, length of follow-up, and composite endpoints including cardiac death (CD) and non-fatal myocardial infarction (NFMI) were recorded. 1:1 propensity score matched analysis was also performed. RESULTS: Over a mean follow-up period of 4.4±2.5 years, there were 132 composite endpoints (75 CD and 57 NFMI) with an event rate of 2.3%. Mean Hcy level was 9.9±4.3 µmol/L (normal Hcy 7.9±1.5 µmol/L and elevated Hcy 13.9±5.1 µmol/L). Kaplan-Meier survival analysis showed an association of elevated Hcy level with worse prognosis (p<0.0001). In addition, a multivariate Cox regression analysis showed an association of elevated Hcy level with worse prognosis for both the entire cohort (hazard ratio [HR] 2.077, 95% confidence interval [CI] 1.467-2.941, p<0.0001) and the propensity score matched cohort (HR 1.982, 95% CI 1.305-3.009, p=0.001). CONCLUSION: Elevated Hcy level is associated with worse outcomes in Korean patients with CAD.

Left Ventricular Filling Pressure as Assessed by the E/e' Ratio Is a Determinant of Atrial Fibrillation Recurrence after Cardioversion

PURPOSE: Left ventricular (LV) filling pressure affects atrial fibrillation (AF) recurrence. We investigated the relationship between diastolic dysfunction and AF recurrence after cardioversion, and whether LV filling pressure was predictive of AF recurrence. MATERIALS AND METHODS: Sixty-six patients (mean 58+/-12 years) with newly diagnosed persistent AF were retrospectively enrolled. We excluded patients with left atrial (LA) diameters larger than 50 mm, thereby isolating the effect of LV filling pressure. We evaluated the differences between the patients with (group 1) and without AF recurrence (group 2). RESULTS: Group 1 showed increased LA volume index (LAVI) and E/e' compared to group 2 (p9.15) compared with patients with lower LV filling pressure (E/e'< or =9.15) (log rank p=0.008). Cox regression analysis revealed that E/e' [hazards ratio (HR): 1.100, 95% CI: 1.017-1.190] and LAVI (HR: 1.042, 95% CI: 1.002-1.084) were independent predictors for AF recurrence after cardioversion. CONCLUSION: LV filling pressure predicts the risk of AF recurrence in persistent AF patients after cardioversion.

A Novel Approach for Identifying Ischemic Cardiomyopathy

No abstract available.

Carotid Artery End-Diastolic Velocity and Future Cerebro-Cardiovascular Events in Asymptomatic High Risk Patients

BACKGROUND AND OBJECTIVES: Prognostic value of additional carotid Doppler evaluations to carotid intima-media thickness (IMT) and plaque has not been completely evaluated. SUBJECTS AND METHODS: A total of 1119 patients with risk factors for, but without, overt coronary artery disease (CAD), who underwent both carotid ultrasound and Doppler examination were included in the present study. Parameters of interest included peak systolic and end-diastolic velocities, resistive indices of the carotid arteries, IMT, and plaque measurements. The primary end-point was all-cause cerebro-cardiovascular events (CVEs) including acute myocardial infarction, coronary revascularization therapy, heart failure admission, stroke, and cardiovascular death. Model 1 covariates comprised age and sex; Model 2 also included hypertension, diabetes and smoking; Model 3 also had use of aspirin and statin; and Model 4 also included IMT and plaque. RESULTS: The mean follow-up duration was 1386+/-461 days and the mean age of the study population was 60+/-12 years. Amongst 1119 participants, 43% were women, 57% had a history of hypertension, and 23% had diabetes. During follow-up, 6.6% of patients experienced CVEs. Among carotid Doppler parameters, average common carotid artery end-diastolic velocity was the independent predictor for future CVEs after adjustments for all models variables (HR 0.95 per cm/s, 95% confident interval 0.91-0.99, p=0.034 in Model 4) and significantly increased the predictive value of Model 4 (global chi2=59.0 vs. 62.8, p=0.029). CONCLUSION: Carotid Doppler measurements in addition to IMT and plaque evaluation are independently associated with future CVEs in asymptomatic patients at risk for CAD.

Relationship between Myocardial Extracellular Space Expansion Estimated with Post-Contrast T1 Mapping MRI and Left Ventricular Remodeling and Neurohormonal Activation in Patients with Dilated Cardiomyopathy

OBJECTIVE: Post-contrast T1 values are closely related to the degree of myocardial extracellular space expansion. We determined the relationship between post-contrast T1 values and left ventricular (LV) diastolic function, LV remodeling, and neurohormonal activation in patients with dilated cardiomyopathy (DCM). MATERIALS AND METHODS: Fifty-nine patients with DCM (mean age, 55 +/- 15 years; 41 males and 18 females) who underwent both 1.5T magnetic resonance imaging and echocardiography were enrolled. The post-contrast 10-minute T1 value was generated from inversion time scout images obtained using the Look-Locker inversion recovery sequence and a curve-fitting algorithm. The T1 sample volume was obtained from three interventricular septal points, and the mean T1 value was used for analysis. The N-Terminal pro-B-type natriuretic peptide (NT-proBNP) level was measured in 40 patients. RESULTS: The mean LV ejection fraction was 24 +/- 9% and the post-T1 value was 254.5 +/- 46.4 ms. The post-contrast T1 value was significantly correlated with systolic longitudinal septal velocity (s'), peak late diastolic velocity of the mitral annulus (a'), the diastolic elastance index (Ed, [E/e']/stroke volume), LV mass/volume ratio, LV end-diastolic wall stress, and LV end-systolic wall stress. In a multivariate analysis without NT-proBNP, T1 values were independently correlated with Ed (beta = -0.351, p = 0.016) and the LV mass/volume ratio (beta = 0.495, p = 0.001). When NT-proBNP was used in the analysis, NT-proBNP was independently correlated with the T1 values (beta = -0.339, p = 0.017). CONCLUSION: Post-contrast T1 is closely related to LV remodeling, diastolic function, and neurohormonal activation in patients with DCM.

The Clinical Impact of Bedside Contrast Echocardiography in Intensive Care Settings: A Korean Multicenter Study

BACKGROUND AND OBJECTIVES: We assessed the ability of portable echocardiography (with contrasts) to clearly delineate the cardiac structure, and evaluated the impact of its use on the diagnosis and management of critically ill patients in Korea. SUBJECTS AND METHODS: We prospectively enrolled 123 patients (mean age 66+/-16 years), who underwent portable transthoracic echocardiography (with contrast) for image enhancement at 12 medical centers. The quality of the global left ventricular (LV) images, the number of the regional LV segments visualized, the ability to visualize the LV apex and the right ventricle (RV), and any changes in the diagnostic procedure and treatment strategy were compared before and after the contrast. RESULTS: Of the 123 patients, 52 (42%) were using mechanical ventilators. The amount of poor or uninterpretable images decreased from 48% to 5% (p<0.001), after the contrast. Before the contrast, 15.6+/-1.1 of 16 LV segments were seen, which improved to 15.9+/-0.6 segments (p=0.001) after the contrast. The ability to visualize the LV apex increased from 47% to 94% (p<0.001), while the inability to clearly visualize the RV decreased from 46% to 19% (p<0.001). Changes in the diagnostic procedure (for example, not requiring other types of imaging studies) were observed in 18% of the patients, and the treatment plan (medication) was altered in 26% of patients after the contrast echocardiography. CONCLUSION: The use of a contrast agent during the portable echocardiography, in intensive care settings, can improve the image quality and impact the diagnostic procedures and treatment for Korean patients.

Erratum: Relationship between Myocardial Extracellular Space Expansion Estimated with Post-Contrast T1 Mapping MRI and Left Ventricular Remodeling and Neurohormonal Activation in Patients with Dilated Cardiomyopathy

The publisher and authors would like to draw the reader's attention to an error.

2014 Korean Guidelines for Appropriate Utilization of Cardiovascular Magnetic Resonance Imaging: A Joint Report of the Korean Society of Cardiology and the Korean Society of Radiology

Cardiac magnetic resonance (CMR) imaging is now widely used in several fields of cardiovascular disease assessment due to recent technical developments. CMR can give physicians information that cannot be found with other imaging modalities. However, there is no guideline which is suitable for Korean people for the use of CMR. Therefore, we have prepared a Korean guideline for the appropriate utilization of CMR to guide Korean physicians, imaging specialists, medical associates and patients to improve the overall medical system performances. By addressing CMR usage and creating these guidelines we hope to contribute towards the promotion of public health. This guideline is a joint report of the Korean Society of Cardiology and the Korean Society of Radiology.

Lipoprotein-Associated Phospholipase A2 Is Related to Plaque Stability and Is a Potential Biomarker for Acute Coronary Syndrome

PURPOSE: Plasma lipoprotein-associated phospholipase A2 (Lp-PLA2) binds to low-density lipoprotein. The levels of Lp-PLA2 reflect the plaque burden, and are upregulated in acute coronary syndrome (ACS). We investigated the diagnostic value of Lp-PLA2 levels and found that it might be a potential biomarker for ACS. MATERIALS AND METHODS: We classified 226 study participants into three groups: patients without significant stenosis (control group), patients with significant stenosis with stable angina (SA group), and patients with ACS (ACS group). RESULTS: Lp-PLA2 and high-sensitivity C-reactive protein (hs-CRP) levels were significantly greater in the ACS group than in the SA group (p=0.044 and p=0.029, respectively). Multivariate logistic regression analysis revealed that Lp-PLA2 levels are significantly associated with ACS (odds ratio=1.047, p=0.013). The addition of Lp-PLA2 to the ACS model significantly increased the global chi2 value over traditional risk factors (28.14 to 35.602, p=0.006). The area under the receiver operating characteristic curve for Lp-PLA2 was 0.624 (p=0.004). The addition of Lp-PLA2 level to serum hs-CRP concentration yielded an integrated discrimination improvement of 0.0368 (p=0.0093, standard error: 0.0142) and improved the ability to diagnose ACS. CONCLUSION: Lp-PLA2 levels are related to plaque stability and might be a diagnostic biomarker for ACS.

Accurate and Reproducible Measurements of Right Ventricular Function in Daily Practice

No abstract available.

2014 Korean Guidelines for Appropriate Utilization of Cardiovascular Magnetic Resonance Imaging: A Joint Report of the Korean Society of Cardiology and the Korean Society of Radiology

Cardiac magnetic resonance (CMR) imaging is now widely used in several fields of cardiovascular disease assessment due to recent technical developments. CMR can give physicians information that cannot be found with other imaging modalities. However, there is no guideline which is suitable for Korean people for the use of CMR. Therefore, we have prepared a Korean guideline for the appropriate utilization of CMR to guide Korean physicians, imaging specialists, medical associates and patients to improve the overall medical system performances. By addressing CMR usage and creating these guidelines we hope to contribute towards the promotion of public health. This guideline is a joint report of the Korean Society of Cardiology and the Korean Society of Radiology.

Diagnosis of Acute Global Myocarditis Using Cardiac MRI with Quantitative T1 and T2 Mapping: Case Report and Literature Review

The diagnosis of myocarditis can be challenging given that symptoms, clinical exam findings, electrocardiogram results, biomarkers, and echocardiogram results are often non-specific. Endocardial biopsy is an established method for diagnosing myocarditis, but carries the risk of complications and false negative results. Cardiac magnetic resonance imaging (MRI) has become the primary non-invasive imaging tool in patients with suspected myocarditis. Myocarditis can be diagnosed by using three tissue markers including edema, hyperemia/capillary leak, and necrosis/fibrosis. The interpretation of cardiac MR findings can be confusing, especially when the myocardium is diffusely involved. Using T1 and T2 maps, the diagnosis of myocarditis can be made even in cases of global myocarditis with the help of quantitative analysis. We herein describe a case of acute global myocarditis which was diagnosed by using quantitative T1 and T2 mapping.

Effect of Abciximab on the Levels of Circulating Microparticles in Patients with Acute Myocardial Infarction Treated by Primary Angioplasty

BACKGROUND AND OBJECTIVES: We investigated the effect of the additional use of abciximab during percutaneous coronary intervention (PCI) on the level of procoagulant microparticles (MPs) in patients with ST-segment elevation myocardial infarction (STEMI) who had undergone primary PCI. SUBJECTS AND METHODS: In this study, we studied 86 patients with STEMI (72 men, age 58+/-13) who had undergone primary PCI. The decision to administer abciximab immediately prior to PCI was left to the discretion of the operator. Blood samples for analysis of MPs were obtained from the femoral artery before and after PCI. MPs with procoagulant potential were measured using a commercial kit. The cellular origins of MPs were determined by antigenic capture with specific antibodies. RESULTS: Procoagulant MPs captured onto annexin V were not changed significantly after PCI {13.4+/-13.2 nM vs. 13.2+/-16.1 nM phosphatidylserine equivalent (PS eq), p=0.479}. Abciximab was used in 30 of 86 patients (35%) immediately prior to PCI. In patients who had undergone PCI without abciximab, no significant change in the level of MPs was observed after PCI. However, in the abciximab group, the level of circulating MPs was significantly decreased after PCI (12.0+/-10.7 nM vs. 7.8+/-11.7 nM PS eq, p=0.018). Levels of endothelial- and platelet-derived MPs also showed a significant reduction after PCI in the abciximab group. CONCLUSION: Primary PCI with additional abciximab significantly reduced the level of procoagulant MPs regardless of their cellular origins in patients with STEMI.

Severe Mitral Regurgitation Due to Coronary Vasospasm, Confirmed by Ergonovine Echocardiography / 영남의대학술지

The common causes of organic mitral regurgitation (MR) include mitral valve prolapse (MVP) syndrome, rheumatic heart disease, and endocarditis. MR also occurs secondary to dilated cardiomyopathy and coronary artery disease. In acute severe MR, the hemodynamic overload often cannot be tolerated, and mitral valve repair or replacement must be performed immediately. We report herein a case of severe MR due to coronary vasospasm that was confirmed via ergonovine echocardiography in a 70-year-old man. He was scheduled to undergo mitral valve surgery, but it did not push through and he was put on medical therapy.