Sahng Lee

Feasibility of two-dimensional global longitudinal strain and strain rate imaging for the assessment of left atrial function: a study in subjects with a low probability of cardiovascular disease and normal exercise capacity.

Background: Two‐dimensional (2D) speckle imaging has shown that it could evaluate not only regional but also global strain (ɛ) and strain rate (SR) of the left and right ventricles. There are no data for global ɛ/SR imaging for left atrial (LA) function evaluation. Methods: A total of 54 subjects (37 men; mean age, 44 ± 10 years) with normal treadmill exercise stress echocardiography and no coronary risk factors were enrolled. Global longitudinal LA ɛ/SR data obtained by 2D speckle imaging with automated software (EchoPAC, GE Medical) were compared with LA volumetric parameters. Results: LA ɛ/SR imaging was acceptable in all patients. Bland‐Altman analysis for these parameters showed no evidence of any systematic difference regarding inter‐ and intraobserver variabilities. Global longitudinal LA strain during systole and peak systolic global longitudinal LA SR were correlated with LA total emptying fraction (EF) (r = 0.399, P = 0.004; r = 0.366, P = 0.008). Global longitudinal LA strain during early diastole and peak early diastolic global longitudinal LA SR were correlated significantly with LA passive EF (r = 0.476, P < 0.001; r = 0.507, P < 0.001). Global longitudinal LA strain during late diastole and peak late diastolic global longitudinal LA SR were not correlated with LA active EF (r = 0.198, P = 0.163; r = 0.265, P = 0.060). Conclusions: Global longitudinal LA ɛ/SR parameters determined by 2D speckle tracking echocardiography are feasible and reproducible indices for the evaluation of LA function. (ECHOCARDIOGRAPHY, Volume 26, November 2009)

Effects of atorvastatin pretreatment on infarct size in patients with ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention

BACKGROUND Atorvastatin pretreatment has been reported to reduce myocardial damage in patients undergoing percutaneous coronary intervention (PCI). We sought to investigate the effect of atorvastatin pretreatment on infarct size in patients with ST-segment elevation myocardial infarction (STEMI). METHODS Patients undergoing primary PCI for ST-segment elevation myocardial infarction within 12 hours after symptom onset were randomized to an atorvastatin group (80 mg before PCI and for 5 days after PCI [n = 89]) or a control group (10 mg daily after PCI [n = 84]). The primary end point was infarct size measured by technetium Tc 99m tetrofosmin single-photon emission computed tomography between days 5 and 14. RESULTS Baseline clinical, angiographic, and procedural characteristics were not significantly different between groups except for age and current smoking status. There was no significant difference in infarct size (as a percentage of the left ventricle) between groups (22.2% ± 15.5% in the atorvastatin group vs 21.6% ± 15.4% in the control group, P = .79). The median infarct size was 19.0% (interquartile range 9.0-32.0) in the atorvastatin group and 18.0% (9.3-32.5) in the control group (P = .76). Achievement of myocardial blush grade 2/3 and complete ST-segment resolution at 60 minutes after PCI occurred with similar frequency (72.8% vs 81.9%, P = .33 and 43.2% vs 47.5%, P = .57, respectively). CONCLUSIONS Pretreatment with high-dose atorvastatin followed by further treatment for 5 days did not reduce infarct size measured by single-photon emission computed tomography in patients undergoing primary PCI.

Efficacy of losartan and carvedilol on central hemodynamics in hypertensives: a prospective, randomized, open, blinded end point, multicenter study.

Renin–angiotensin system (RAS) blockers have shown clinical outcomes superior to those of the beta (β)-blocker atenolol, despite similar reductions in the peripheral blood pressure (BP), perhaps because of different impacts on central hemodynamics. However, few comparative studies of RAS blockers and newer vasodilating β-blockers have been performed. We compared the central hemodynamic effects of losartan and carvedilol in a prospective, randomized, open, blinded end point study. Of the 201 hypertensive patients enrolled, 182 (49.6±9.9 years, losartan group=88 and carvedilol group=94) were analyzed. Carotid-femoral pulse wave velocity (cfPWV), aortic augmentation index (AIx), AIx corrected for a heart rate (HR) of 75 beats per minute (AIx@HR75) and central BP were measured noninvasively at baseline and after a 24-week treatment regimen with losartan or carvedilol. After 24 weeks, there were no between-group differences in the brachial BP, cfPWV, AIx@HR75 or central BP changes, except for a more favorable AIx effect with losartan. The changes in all measured metabolic and inflammatory parameters were also not significantly different between the two groups, except for uric acid. Losartan and carvedilol showed generally comparable effects on central hemodynamic indices, metabolic profile, inflammatory parameters and peripheral arterial pressure with a 24-week treatment.

Relation of ruptured plaque culprit lesion phenotype and outcomes in patients with ST elevation acute myocardial infarction.

We used virtual histology intravascular ultrasound (VH-IVUS) to assess culprit plaque rupture in 172 patients with ST-segment elevation acute myocardial infarction. VH-IVUS-defined thin-capped fibroatheroma (VH-TCFA) had necrotic core (NC) > 10% of plaque area, plaque burden > 40%, and NC in contact with the lumen for ≥ 3 image slices. Ruptured plaques were present in 72 patients, 61% of which were located in the proximal 30 mm of a coronary artery. Thirty-five were classified as VH-TCFA and 37 as non-VH-TCFA. Vessel size, lesion length, plaque burden, minimal lumen area, and frequency of positive remodeling were similar in VH-TCFA and non-VH-TCFA. However, the NC areas within the rupture sites of VH-TCFAs were larger compared to non-VH-TCFAs (p = 0.002), while fibrofatty plaque areas were larger in non-VH-TCFAs (p < 0.0001). Ruptured plaque cavity size was correlated with distal reference lumen area (r = 0.521, p = 0.00002), minimum lumen area (r = 0.595, p < 0.0001), and plaque area (r = 0.267, p = 0.033). Sensitivity and specificity curve analysis showed that a minimum lumen area of 3.5 mm2, a distal reference lumen area of 7.5 mm2, and a maximum NC area of 35% best predicted plaque rupture. Although VH-TCFA (35 of 72) was the most frequent phenotype of plaque rupture in ST-segment elevation myocardial infarction, plaque rupture also occurred in non-VH-TCFA: pathologic intimal thickening (8 of 72), thick-capped fibroatheroma (1 of 72), and fibrotic (14 of 72) and fibrocalcified (14 of 72) plaque. In conclusion, not all culprit plaque ruptures in patients with ST-segment elevation myocardial infarction occur as a result of TCFA rupture; a prominent fibrofatty plaque, especially in a proximal vessel, may be another form of vulnerable plaque. Further study should identify additional factors causing plaque rupture.

Nodular Excision for Painful Localized Achilles Tendon Xanthomas in Type II Hyperlipoproteinemia: A Case Report

Achilles tendon xanthomas are often associated with type II hyperlipoproteinemia, in which low-density lipoprotein derived from the circulation accumulates in the tendons. Sometimes coronary artery disease can jeopardize the life of the patient if the condition is neglected. We describe the case of bilateral painful Achilles tendon xanthomas in a heterozygous type II hyperlipoproteinemia family. Her symptoms were not alleviated despite anti-inflammatory medication and eccentric exercise for 6 months. She was treated with nodular excision of the xanthomas bilaterally and then with postoperative statins to avoid recurrence.

A Case of Acute Thrombotic Occlusion of an Anomalous Origin of the Right Coronary Artery From the Left Coronary Sinus: Focus on the Importance of Dual-Source Computed Tomography for Failed Emergency Coronary Angiography

Coronary artery anomalies in patients undergoing coronary angiography are often technically challenging for invasive cardiologists and may delay revascularization time. We report a patient who underwent successful bailout revascularization using dual-source computed tomography after failed emergency angiography. This case emphasizes the utility of dual-source computed tomography, especially in an urgent clinical setting, for allowing interventional cardiologists to rapidly identify and effectively treat the aberrant coronary artery.

Valsartan 160 mg/Amlodipine 5 mg Combination Therapy versus Amlodipine 10 mg in Hypertensive Patients with Inadequate Response to Amlodipine 5 mg Monotherapy

Background and Objectives When monotherapy is inadequate for blood pressure control, the next step is either to continue monotherapy in increased doses or to add another antihypertensive agent. However, direct comparison of double-dose monotherapy versus combination therapy has rarely been done. The objective of this study is to compare 10 mg of amlodipine with an amlodipine/valsartan 5/160 mg combination in patients whose blood pressure control is inadequate with amlodipine 5 mg. Subjects and Methods This study was conducted as a multicenter, open-label, randomized controlled trial. Men and women aged 20-80 who were diagnosed as having hypertension, who had been on amlodipine 5 mg monotherapy for at least 4 weeks, and whose daytime mean systolic blood pressure (SBP) ≥135 mmHg or diastolic blood pressure (DBP) ≥85 mmHg on 24-hour ambulatory blood pressure monitoring (ABPM) were randomized to amlodipine (A) 10 mg or amlodipine/valsartan (AV) 5/160 mg group. Follow-up 24-hour ABPM was done at 8 weeks after randomization. Results Baseline clinical characteristics did not differ between the 2 groups. Ambulatory blood pressure reduction was significantly greater in the AV group compared with the A group (daytime mean SBP change: -14±11 vs. -9±9 mmHg, p<0.001, 24-hour mean SBP change: -13±10 vs. -8±8 mmHg, p<0.0001). Drug-related adverse events also did not differ significantly (A:AV, 6.5 vs. 4.5 %, p=0.56). Conclusion Amlodipine/valsartan 5/160 mg combination was more efficacious than amlodipine 10 mg in hypertensive patients in whom monotherapy of amlodipine 5 mg had failed.

Thoracic endovascular aortic repair with the chimney technique for blunt traumatic pseudoaneurysm of the aortic arch in a no-option patient.

A 42-year-old man was involved in a motor vehicle collision. Imaging studies revealed the presence of a post-traumatic aortic pseudo-aneurysm (about 34×26 cm) arising from the descending thoracic aorta at the level of the left subclavian artery (LSA), prone to rupture. Thoracic endovascular aneurysm repair (TEVAR) was the only feasible option due to his poor overall medical status. In this case, LSA needed to be covered in order to extend the proximal landing zone. Eventually, modified TEVAR was successfully performed by means of the chimney technique to preserve flow to the LSA and to prevent flow into the pseudoaneurysmal sac.

Hybrid Approach for the Treatment of Thoracic Aortic Arch Aneurysm in a Patient With Chronic Obstructive Lung Disease and Retrosternal Adhesion

A 73-year-old woman with a history of chronic hypertension and severe chronic obstructive pulmonary disease, presented to a district general hospital with thoracic pain in a profound state of shock. She was diagnosed with cardiac tamponade, severe mitral regurgitation, and Stanford type A (Debakey type I) intramural hematoma. Her ascending aorta was of a significant size and therefore emergent repair was done to replace the ascending aorta and mitral valve. After 6 months, an increased aneurysmal size of 6.0 cm was observed in a follow up contrast-enhanced computed tomography angiography. The patient was successfully treated by a staged hybrid procedure involving initial supra-aortic reconstruction.