1.Theoretical prediction of side branch compromise after main branch stenting in coronary bifurcation
Journal of Geriatric Cardiology 2008;5(2):91-100
One of the main problems of treatment of bifurcation lesions is side branch (SB) stenosis appearing after stent placement in the main vessel.The aim of this study was to create quantitative method for prediction of side branch compromise extent.We accepted that the main mechanism for SB ostial stenosis is flow divider (FD) displacement from stent struts after stent implantation in the main vessel.Using easily measurable parameters from coronary angiography,as SB diameter,angle α (initial angle between axes of parent vessel and SB axis) and angle α' (angle between above mentioned axes after stent placement) we can calculate percentage diameter stenosis at branch ostium (%DS):%DS = sin (α - α')/(tan α).In boundary condition of full FD displacement %DS = cos α.We tested our theoretical predictions with fluoroscopic observation of elastic wall model of bifurcation (45°distal angle between branches)permitting wall deformations with stent.There is full coincidence of values of %DS and percentage area stenosis (%AS).The regular formulas for calculations of %DS and %AS overestimate stenosis severity between 10% and 25%.Our model tests have shown full coincidence between predicted values for %DS and observed values.We demonstrate that part of the SB ostium is not visible in regular angiography and contributes to ostial lumen area.This is a method that permits quantitative prediction of side branch compromise.
2.Changes in coronary bifurcations after stent placement in the main vessel and balloon opening of stent cells:theory and practical verification on a bench-test model
Journal of Geriatric Cardiology 2008;5(1):43-49
Objective To describe changes that occur in stent morphology and structure after its implantation in coronary bifurcation.Side branch (SB) compromise after stenting of main vessel in coronary bifurcation is a major intraprocedural problem and for the long term,as a place of restenosis.Methods We created an elastic wall model (parent vessel diameter 3.5mm,daughter branches 3.5mm and 2.75mm)with 30,45 and 60 degree distal angulation between branches.After stent implantation,struts to the side branch were opened with 2.0mm and consequently 3.0mm diameter balloons.Subsequent balloon redilatations and kissing balloon inflations (KBI) were performed.All stages of the procedure were photographed with magnification up to 100 times.Results We found that the leading mechanism for side branch compromise was carina displacement,and discovered theoretical description for expected ostial stenosis severity.Based on our model we found that displacement of bifurcation flow divider cause SB stenosis with almost perfect coincidence with our theoretical predictions.Opening of stent cells through the proximal and distal stent struts always increased interslrut distance,but never achieved good apposition to the wall.Balloon diameter increase didn't give proportional enlargement in stent cell diameters.KBI leads to some small better stent positioning,correcting main vessel strut dislodgment from wall,but never gave full strut-wall contact.Distance between struts and wall was minimal only when the stent cell perfectly faced ostium of SB.This was also our observation that the shape of ostium of SB becomed eUiptically-bean shaped after stent implantation and generally kept that shape during consequent stages of experiment.Measured diameter and area stenosis were perfectly fitted and theoretically predicted from our concept Conclusion We have described stent-wall deformations in stent-balloon technique for treatment of coronary bifurcation demonstrating carina displacement as possibly main mechanism of side branch compromise after main vessel stenting.We have shown that KBI could not give full strut-wall contact if there is no perfect facing of stem cell and SB ostium.(J Geroatr Cardool 2008;5(1):43-49)
3.QT hysteresis in long-QT syndrome children with exercise testing.
Dong-sheng GAO ; Wei-yi FANG ; Christine CHIU-MAN ; Joel KIRSH ; Gil GROSS ; Robert M HAMILTON
Chinese Medical Journal 2007;120(3):179-182
BACKGROUNDCongenital long QT syndrome (LQTS) is an inherited ion channel disorder resulting in abnormal cardiac repolarization that can cause syncope and sudden death associated with a prolonged rate-corrected QT interval and polymorphic ventricular tachycardia. Several studies in adults showed that LQTS patients have altered QT adaptation to heart rate changes compared with normal subjects which forming a "hysteresis loop" in the QT-circle length plot. This study was to observe the QT interval changing during exercise testing in children long QT syndrome (LQTS) patients, explore the new diagnosis methods of LQTS.
METHODSThe subjects were divided into 3 groups according to 1993 LQTS diagnostic criteria. Group 1: LQTS group (n = 17) who scored > or = 4 points indicating definite LQTS. Group 2: Middle group (n = 16), patients who have prolonged QT interval but scored 1.5 to 3.5. Group 3: Normal control group (n = 18). The average age of all study population is (12.3 +/- 5.8) years. No case had beta-adrenergic antagonists administration before exercise testing. All subjects were underwent tread mill exercise testing and electrocardiograph in whole exercise testing and recovery were recorded. QT and heart rate changing during whole exercise testing period were recorded. DeltaQT, the QT interval at 1, 2, 4, 6 minutes into recovery subtract from the QT interval at a similar heart rate during exercise, were calculated.
RESULTSIn all three groups, QT intervals were shortening with the increasing of heart rate, but QTc had no significant change. DeltaQT at 1 minute ((45 +/- 11) ms), 2 minutes ((37 +/- 15) ms), 4 minutes ((23 +/- 12) ms) into recovery in LQTS group were significantly greater than that of the other two groups (P < 0.05, P < 0.01, P < 0.01, respectively). There was no DeltaQT significant difference between middle group and normal control group at recovery time. During the recovery phase in LQTS group, the QT interval remained shortened despite a decelerating heart rate, forming a hysteresis "loop" in the curve relating the QT interval to the cycle length.
CONCLUSIONSIn children LQTS patients, there is significant QT hysteresis loop in the relation of QT interval with heart rate during recovery of exercise testing, which could be useful to the early diagnosis for LQTS.
Adolescent ; Child ; Electrocardiography ; Exercise Test ; Female ; Heart Rate ; Humans ; Long QT Syndrome ; physiopathology ; Male
5.Quantifications of Lipid Kinetics In Vivo Using Stable Isotope Tracer Methodology
Il Young KIM ; Sanghee PARK ; Jiwoong JANG ; Robert R WOLFE
Journal of Lipid and Atherosclerosis 2020;9(1):110-123
Like other bodily materials, lipids such as plasma triacylglycerol, cholesterols, and free fatty acids are in a dynamic state of constant turnover (i.e., synthesis, breakdown, oxidation, and/or conversion to other compounds) as essential processes for achieving dynamic homeostasis in the body. However, dysregulation of lipid turnover can lead to clinical conditions such as obesity, fatty liver disease, and dyslipidemia. Assessment of “snap-shot†information on lipid metabolism (e.g., tissue contents of lipids, abundance of mRNA and protein and/or signaling molecules) are often used in clinical and research settings, and can help to understand one's health and disease status. However, such “snapshots†do not provide critical information on dynamic nature of lipid metabolism, and therefore may miss “true†origin of the dysregulation implicated in related diseases. In this regard, stable isotope tracer methodology can provide the in vivo kinetic information of lipid metabolism. Combining with “static†information, knowledge of lipid kinetics can enable the acquisition of in depth understanding of lipid metabolism in relation to various health and disease status. This in turn facilitates the development of effective therapeutic approaches (e.g., exercise, nutrition, and/or drugs). In this review we will discuss 1) the importance of obtaining kinetic information for a better understanding of lipid metabolism, 2) basic principles of stable isotope tracer methodologies that enable exploration of “lipid kinetics†in vivo, and 3) quantification of some aspects of lipid kinetics in vivo with numerical examples.
6.Percutaneous transmyocardial revascularization induces angiogenesis: a histologic and 3-dimensional micro computed tomography study.
Hyuck Moon KWON ; Bum Kee HONG ; Gil Jin JANG ; Dong Soo KIM ; Eui Young CHOI ; In Jai KIM ; Charles J MCKENNA ; Eric L RITMAN ; Robert S SCHWARTZ
Journal of Korean Medical Science 1999;14(5):502-510
The purpose of this study was to visualize the spatial patterns and connection of channels created after percutaneous transmyocardial revascularization (PTMR) in normal porcine hearts, and to estimate the relative contributions of transmyocardial and coronary perfusion. Six pigs underwent PTMR creating channels using radiofrequency ablative energy. Three-dimensional computed tomography imaging of channels 1 hr after PTMR showed the direct connection of PTMR channels to the myocardial capillary network and to epicardial coronary vessels. In the heart, examined 28 day after PTMR, there was a fine, extensive, network of microvessels originating from the site of the original PTMR channel, also connecting the left ventricular cavity to myocardial capillaries. Histopathologic examination of the 1-hr specimens showed numerous regions of myocardial hemorrhage and associated inflammatory cell infiltration. In the 28-day specimens, newly developed new vascular network suggested neovascularization within the core of these channel remnants. The immunoreactivity for basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF) were intense within myocardium and neovascular structure surrounding PTMR channel remnants. The vascular connections occur by direct communication with existing myocardial vasculature acutely, and angiogenesis in these channel remnant chronically.
Animal
;
Coronary Angiography
;
Coronary Circulation
;
Coronary Vessels/pathology
;
Heart/radiography*
;
Heart Ventricle/radiography
;
Image Enhancement/methods
;
Immunohistochemistry
;
Myocardial Revascularization/methods*
;
Myocardium/pathology*
;
Neovascularization, Pathologic/radiography
;
Neovascularization, Pathologic/pathology*
;
Perfusion
;
Swine
;
Tomography, X-Ray Computed
7.Factors associated with utilization of primary preventive services of Tamang Serbisyo para sa Kalusugan ng Pamilya (TSeKaP) among PhilHealth indigent members in Manila.
Allan John R. BARCENA ; Carl Robert A. CASIMIRO ; Gil Dominic R. CATALAN ; Camille A. PESTANO ; Fenny Mariechit Q. QUINTO ; Buenalyn Teresita M. RAMOS-MORTEL
Acta Medica Philippina 2018;52(3):245-252
BACKGROUND: The primary preventive services of TSeKaP promote disease prevention among marginalized groups. The threat of non-utilization, however, undermines the effective implementation of the program. To fill in the knowledge gap regarding utilization of primary preventive services, rate of utilization and factors associated with utilization of primary preventive services must be determined.
OBJECTIVE: To determine the rate of utilization and the association of selected factors with utilization of primary preventive services of TSeKaP among PhilHealth Indigent Member of Manila.
METHODS: Using a two-stage cluster sampling, 145 PhilHealth Indigent Members were randomly selected and interviewed. Chi-square test and Fisher's exact test were used to determine associations. FGDs were also conducted to gather reasons related to utilization.
RESULTS AND CONCLUSION: Among those surveyed, 68.28% were found to have utilized at least one primary preventive service. Age (p-value=0.021), knowledge (p-value=0.015), familiarity (p-value=0.029), and accessibility (p-value=0.013) were found to be associated with utilization. Utilization generally increases as the age group increases. Those with satisfactory knowledge on TSeKaP, those familiar with their health center, and those who report that their health center is accessible were 1.45 times, 2.12 times and 2.83 times more likely to utilize than their counterparts, respectively. Results showing a significant proportion of non-utilization emphasize the need to improve implementation strategies by improving not only the knowledge of respondents' on TSeKaP but also their familiarity with their health centers. The use of various communication channels, such as barangay bulletin, public address system, radio or television, may aid the dissemination of pertinent information regarding the program as perceived by the respondents.
Human ; Male ; Female ; Aged 80 And Over ; Aged (a Person 65 Through 79 Years Of Age) ; Middle Aged (a Person 45-64 Years Of Age) ; Health Promotion ; Preventive Health Services ; Health Services, Indigenous ; Facilities And Services Utilization