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This paper aimed to study the effect of Dalbergia cochinchinensis heartwood on plasma endogenous metabolites in rats with ligation of the left anterior descending coronary artery, and to analyze the mechanism of D. cochinchinensis heartwood in improving acute myocardial ischemic injury. The stability and consistency of the components in the D. cochinchinensis heartwood were verified by the establishment of fingerprint, and 30 male SD rats were randomly divided into a sham group, a model group, and a D. cochinchinensis heartwood(6 g·kg~(-1)) group, with 10 rats in each group. The sham group only opened the chest without ligation, while the other groups established the model of ligation. Ten days after administration, the hearts were taken for hematoxylin-eosin(HE) staining, and the content of heart injury indexes in the plasma creatine kinase isoenzyme(CK-MB) and lactate dehydrogenase(LDH), energy metabolism-related index glucose(Glu) content, and vascular endothelial function index nitric oxide(NO) was determined. The endogenous metabolites were detected by ultra-high-performance liquid chromatography-time-of-flight-mass spectrometry(UPLC-Q-TOF-MS). The results showed that the D. cochinchinensis heartwood reduced the content of CK-MB and LDH in the plasma of rats to relieve myocardial injury, reduced the content of Glu in the plasma, improved myocardial energy metabolism, increased the content of NO, cured the vascular endothelial injury, and promoted vasodilation. D. cochinchinensis heartwood improved the increase of intercellular space, myocardial inflammatory cell infiltration, and myofilament rupture caused by ligation of the left anterior descending coronary artery. The metabolomic study showed that the content of 26 metabolites in the plasma of rats in the model group increased significantly, while the content of 27 metabolites decreased significantly. Twenty metabolites were significantly adjusted after the administration of D. cochinchinensis heartwood. D. cochinchinensis heartwood can significantly adjust the metabolic abnormality in rats with ligation of the left anterior descending coronary artery, and its mechanism may be related to the regulation of cardiac energy metabolism, NO production, and inflammation. The results provide a corresponding basis for further explaining the effect of D. cochinchinensis on the acute myocardial injury.
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Male , Animals , Rats , Rats, Sprague-Dawley , Dalbergia , Myocardial Ischemia , Metabolomics , Heart , Heart Injuries , Creatine Kinase, MB FormABSTRACT
Acute myocardial infarction is caused by the rupture or erosion of an atherosclerotic plaque, initiating intraluminal thrombosis resulting in partial or complete occlusion of a coronary artery. Primary percutaneous coronary intervention (PCI) is the preferred treatment and is effective in opening the infarct-related artery. These results can be further improved with thrombus aspiration which reduces stent thrombosis and improves myocardial blush. In acute presentation, there is a high load of thrombus in the infarctrelated artery and stent placement in such a case increases the chances of the thrombus shifting both proximally and distally in the microvasculature. In such patient, deferred stenting along with the attempt of thrombus aspiration has the potential for complete thrombus removal with improvement in TIMI flow which eliminates the need of stenting. Here, we present an interesting case report pertaining to the feasibility of multiple thrombus aspiration attempts (>25) as first approach in young patient (Male/32 years/no comorbidities) with late presentation of STEMI and a large resistant thrombus load on an angiogram. We also re-assessed the need of stenting after 5 days of thrombus aspiration attempt along with continued anticoagulation from the first contact with patient.
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Angiographically, a “dual LAD” is described as two distinct arteries supplying the vascular territory of the LAD in parts, identified as the short LAD/LAD1 and the long LAD/LAD2. Using an easy-to-understand three-step approach, Jariwala et al unveiled a novel classification strategy for dual LAD systems in an attempt to decrease ambiguity in diagnosis and management of the anomaly. As part of our research, we looked at a wide range of published cases and case series in the literature, and also those reported from our hospital. In our novel classification system, we divide dual LADs into three main groups based on their origin and vascular territory, each of which is further divided into subgroups based on the course of LAD1/LAD2 and the variable feature that is a distinguishing attribute of the type of anomaly to be specified. A review of 144 publications in the world literature revealed 340 patients eligible for the study. The median age was 58.8 years (SD - 11.42; range - 29e89) with male predominance (3.3:1). Cases in Group I comprised 60.6% of the total cases, followed by Group II (36.2%), and Group III (3.2%). Subgroup I-A was the most common in terms of dual LAD, followed by subgroup II-A. Acute coronary syndrome (45.5%) and chronic coronary syndrome (55.8%) were the most common clinical presentations in patients with significant coronary artery disease (30.8%).
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Myocardial bridging (MB) is a relatively uncommon congenital anomaly where a segment of the coronary artery dips inside the myocardium and takes a tunneled course under a bridge of the myocardium. This leads to the compression of the coronary artery during systole resulting in hemodynamic changes and their clinical manifestations. However, it is an incidental finding but can present with multiple complications like myocardial ischemia, infarction, and sudden death, primarily when associated with other risk factors like left ventricular hypertrophy of the heart. Therefore, a careful examination of the heart is essential for evaluating the clinical significance of the MB. Here, we presented a case of a 30-year-old young female who had a sudden death, and her histological examination of the heart showed MB of left anterior descending coronary artery (LAD).
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Objective:To analysis the clinical features of patients with acute myocardial infarction (AMI) presenting de Winter pattern on electrocardiogram.Methods:A total of 1 287 patients with AMI admitted to Beijing Luhe Hospital between June 2017 and January 2019 were enrolled in the study. Electrocardiogram and clinical features of 13 patients with AMI presenting de Winter pattern on electrocardiogram were analyzed and compared with anterior wall ST-segment elevation myocardial infarction(STEMI, n=206). Results:Among the 13 patients, 12 were males, aged (52.23±12.55) years old. Compared to patients with anterior wall STEMI, the age in the de Winter group was younger [(52.23±12.55)years vs. (59.79±12.46)years; t=-2.12, P=0.03], and the time from onset to appearing a typical ECG was shorter [109.0 (71.5, 152.0)min vs. 200.5 (120.0, 397.5)min; Z=-3.38, P<0.01]. Three cases showed a shifting between de Winter pattern and typical STEMI ECG: the de Winter ECG pattern progressed to STEMI in 2 cases, 1 case changed from STEMI to de Winter,then converted to STEMI again. The emergency angiography was performed in all 13 patients, angiography showed that proximal left anterior descending branch (LAD) was involved in 11 cases, mid LAD was involved in 1 case, and diffuse spasm occurred in all vessels in 1 case. The de Winter ECG pattern vanished in all patients after primary percutaneous coronary intervention or emergency angiography. Conclusions:The de Winter ECG pattern suggests an acute proximal or mid LAD artery occlusion, and the de Winter ECG pattern can be alternated with STEMI. The de Winter pattern should be recognized and revascularization should be given early.
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Objective:To explore the influencing factors of postoperative graft stenosis in patients undergoing left internal mammary artery-left anterior descending branch (LIMA-LAD) coronary artery bypass graft (CABG) surgery.Methods:A retrospective analysis of the clinical data of 86 patients who were admitted to the Second Affiliated Hospital of Hainan Medical College and received coronary angiography after CABG surgery from July 2019 to December 2020 due to recurrent chest tightness, chest pain and other symptoms. According to the degree of stenosis of the LIMA-LAD graft, the patients were divided into stenosis group ( n=25) and non-stenosis group ( n=61). The graft stenosis of patients in the stenosis group was ≥50%, and the graft stenosis of patients in the non-stenotic group was less than 50%. The general information, past medical history, CABG intraoperative data, current visit data and biochemical indicators of the two groups were compared. Measurement data were expressed as mean±standard deviation ( Mean± SD), comparison between groups was by t-test; count data comparison between groups was by Chi-square test. Logistic regression analysis was used to screen out the influencing factors of graft stenosis after CABG. Use the rms package in the R 4.0.2 software to build a nomogram prediction model. Using receiver operating characteristic (ROC) curve to evaluate the discriminative degree of the model. Use the calibration curve and deviation correction C-index to evaluate the nomogram prediction model. Use X-tile software to obtain the cutoff value of the nomogram model integral, use Kaplan-Meier method to draw the survival curve, and use Log-rank to test. Results:Logistic regression analysis showed that smoking, hypertension, pre-CABG left anterior descending branch (LAD) stenosis <75%, pre-CABG left internal mammary artery (LIMA) blood flow, and coronary angiography diffuse lesions are independent risk factors that affect LIMA-LAD graft stenosis after CABG ( P<0.05). The C-index value predicted by the nomogram model was 0.879 (95% CI: 0.818-0.955, P<0.001). The area under the ROC curve was 0.712 (95% CI: 0.594-0.801, P<0.001), with good discrimination. The calibration curve shows that the accuracy of the model prediction was good. Through the X-tile software screening to obtain the model score cutoff value, the patients were divided into low-risk group (≤54 points), medium-risk group (>54 points and ≤112 points), and high-risk group (>112 points). The results of survival analysis showed that the incidence of postoperative graft stenosis in the three groups was 20.9%, 50.0% and 80.0%, respectively. Conclusions:Smoking, hypertension, LAD stenosis before CABG <75%, LIMA blood flow before CABG, and coronary angiography diffuse lessions are independent risk factors that affect LIMA-LAD graft stenosis after CABG. The construction of a nomogram prediction model can provide a reference for evaluating the patency of the LIMA-LAD graft vessel before CABG operation, and reduce the probability of LIMA-LAD graft vessel stenosis after CABG operation.
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de Winter syndrome is a special equivalent of anterior ST-segment elevation myocardial infarction (STEMI) characterized by the absence of overt ST-elevation with upsloping ST-segment depression followed by tall symmetrical T-waves in the precordial leads, often associated with total occlusion of the proximal left anterior descending coronary artery. Herein we present a case of de Winter syndrome in a 63-year-old man, whose initial ECG showed no ST-segment elevation, but subsequent coronary angiography confirmed total occlusion of the proximal LAD coronary artery. The patient was successfully treated via mechanical reperfusion therapy and stenting through percutaneous coronary intervention (PCI). de Winter syndrome is associated with a high mortality often due to insufficient awareness of this condition by clinicians. Immediate reperfusion therapy by PCI is the life-saving treatment for the patients diagnosed with this syndrome, and prompt recognition of the ECG pattern is critical to ensure the timely administration of the therapy.
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Humans , Male , Middle Aged , Coronary Angiography , Coronary Vessels , Electrocardiography , Percutaneous Coronary Intervention , ST Elevation Myocardial InfarctionABSTRACT
In countries like India rheumatic heart disease (RHD) is still a common problem, and with improvements in diagnosis and treatment, the lifespan of these patients is increased. With increase in the lifespan, these patients may develop coronary artery disease (CAD) and present as acute coronary syndrome (ACS). In some cases especially RHD with severe mitral stenosis (MS), thrombus that develop in left atrium may embolize in one of the coronary arteries, leading to acute coronary syndrome. We report a case of 51 year old female who was a known case of rheumatic heart disease and now presented with acute coronary syndrome. Patient was hemodynamically unstable and underwent percutaneous balloon mitral valvotomy (PBMV) and percutaneous coronary intervention (PCI) simultaneously. We here discuss the possible complications that need to be addressed in such scenario and how can we approach such cases. This is first of such intervention at our institute and also there are very few such records available online. Patient tolerated the procedure well with significant clinical improvement.
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BACK GROUND OF STUDY:A detailed awareness of branching pattern of left main coronary artery is of immense help for various diagnostic and therapeutic measures on coronary arteries, in this era of increasing coronary artery disease. MATERIALS & METHODS: Fifty human hearts were included in the study group. The LMCA and its branches were studied in detail after removing the epicardium and subepicardial fat. RESULTS: This dissection study on the ramification of LMCA could detect bifurcation , trifurcation and quadrifurcation in 76%, 22% and 2% respectively.
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Background: The anatomical variations of left coronary artery [LCA] determine the course in the pathogenesis ofatherosclerosis, mechanical stress and hemodynamic change.Aim: To study the gross anatomy of left coronary artery [LCA] in terms of its origin, termination, branchingpattern, dominance pattern, external diameter at origin, length of main trunk of left coronary artery, variationsand/ anomalies if present.Materials and Methods: After an ethical approval, 150 adult human cadaveric hearts were collected fromDepartment of Anatomy, B.V.D.U. Medical College and Hospital, Sangli and Pune. The careful dissection wascarried out to note details about left coronary artery and data was analyzed using SPSS software.Results: The origin of left coronary artery was observed in the left posterior aortic sinus 100%. The incidence ofbifurcation, trifurcation and quadrifurcation was 69.33, 28% and 2.67% respectively. SA nodal artery was directlyarising from main trunk of left coronary artery in 2 hearts (1.33%). Circumflex branch of left coronary artery gaveSA nodal artery, AV nodal artery and posterior interventricular artery in 18.66%, 16% and 16% hearts respectively.In one case (0.66%), we found a hyperdominant left anterior descending artery which continued as posteriorinterventricular artery [PDA] occupying entire posterior interventricular sulcus and terminated at crux of theheart by giving AV nodal artery. Hence left dominance was observed in total 16.66% cases. The mean externaldiameter of left coronary artery at its origin was 5.02 ±1.0328. Length of main trunk of left coronary artery wasranging from 4 mm to 22 mm with mean length of 11.66±3.529 mm.Conclusion: Short or long main trunk of left coronary artery, small diameter of main trunk, additional terminalbranches of left coronary artery, left coronary artery dominance, Mouchet’s posterior recurrent interventricularartery, hyperdominanant left anterior descending artery are the significant anatomical factors which decide theextent of coronary insufficiency, its functional impact and may create challenges during the interventionalcoronary care.
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Aim: This current study is done to throw light upon the, distribution and termination of right coronary artery andleft anterior descending branch of left coronary artery and to correlate the clinical significance of the variationsobservedMaterials and methods: 30 human hearts from the embalmed cadavers from Department of Anatomy, GreatEastern Medical School were collected during routine dissection. The heart is taken out after incising the fibrouspericardium and great vessels .The course of right and left coronary arteries were traced from the Ostia. Thespecimens were duly numbered, preserved in 5% formaldehyde solution. Photographs of each specimen weretaken by digital camera and the arterial pattern is coloured red digitally and labeled.Results: In the present study the right coronary artery terminates at crux or beyond the crux in 57%, before cruxin 23% and right border in 13%. Left anterior descending artery terminates beyond apex in the lower 1/3rd of theinter-ventricular groove in 87% and at the apex in 13%.Conclusion: Right and left coronary arteries showed significant variation in their mode of termination. Betteranatomical knowledge about the branches of coronary artery and its variation is essential for cardiologists andinterpretation of coronary angiograms by radiologist.
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Objective To study the impact of heartbeat on the left ventricular myocardial (mLV) and the left anterior descending (LAD) coronary arterial dosimetry following intensity modulated radiotherapy (IMRT) for left-sided breast carcinoma.Methods A total of 15 female patients who received electrocardiography gated 4D-CT scan in inspiratory breathing-holding were enrolled.According to cardiac cycle,20 time-phase images were reconstructed from 0 to 95％ at 5％ interval.Then,the mLV and the LAD were delineated respectively and the IMRT plans of the left breast carcinoma were generated based on 0％ phase CT images.The volume and dice similarity coefficient (DSC) of the mLV were calculated,and the variation range of the mLV and the LAD dose-volume indexes were compared among different phases.Results The average rate of DSC variation of mLV was eightfold of volume,which reached to 472.07％,and the average change rate of mLV (Dmean) was up to 41.95％.The difference of the mLV's volume and DSC was statistically significant between the maximum and minimum(t =-6.585,-28.870,P＜0.05),as well as the D V10,V20,V30 and V40(t=-5.260,-4.084,-3.592,-3.273,-2.566,P ＜0.05).The average change rate of the LAD's D was up to 130.14％.The difference of D V10,V20,V30 and V40 of LAD was statistically significant between the maximum and minimum(t =-9.758,-8.810,-8.682,-7.853,-6.205,P ＜ 0.05).Conclusions The dosimetry impact of heartbeat on mLV and LAD should not be ignored.
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Objective To study the clinical value of intraoperative epicardial echocardiography ( IEE) in assessing graft-left anterior descending artery ( LAD ) of off-pump coronary artery bypass grafting ( OPCABG) . Methods IEE was used to detecte graft vessels anastomosis in 53 patients with OPCABG-LAD . Two-dimensional grey ultrasound and color Doppler ultrasound was used to show whether there was abnormal echo in proximal and distal lumen , measuring diameter and rate of stenosis . Pulse Doppler ultrasound was used to observe the blood flow spectrum . Intraoperative transient blood flow meter (TTFM) was employed to measure the pulsatility index and flow volume . Results Among the 53 patients with OPCABG-LAD ,38 cases were left internal mammary artery graft (LIMA) ,15 cases were saphenous vein graft (GSV) . Pulsatility index and flow volume showed normal by TTFM . The detection rates of graft vessels-LAD anastomosis in proximal and distal segment were 100％ using IEE , including 10 cases anastomotic plaques and 10 cases proximal plaques . Comparison of blood flow parameter of graft by IEE and TTFM in operation ,there was no significant difference in LIMA grafts ( P =0 .091) ,but the correlation was statistically significant ( r = 0 .809 , P < 0 .001 ) ;the difference in GSV grafts had no statistical significance ( P = 0 .821 ) ,but the correlation was statistically significant ( r = 0 .684 , P = 0 .005 ) . Conclusions IEE clearly displays the lumen of graft vessel and LAD ,and measures the hemodynamic indexes . It provides an intuitive ,accurate and convenient method for detecting the patency of the graft vessels during OPCABG .
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Objective To investigate the risk factors of major adverse cardiac events (MACE) in patients with intermediate coronary stenosis in proximal left anterior descending artery (ICS-PLAD) and to assess the predictive value of risk factors model for MACE in patients with ICS-PLAD.Methods Totally 221 patients with ICS-PLAD (≥50％ and ＜70 ％ diameter stenosis by angiography) were retrospectively studied.The risk factors of MACE in patients with ICS-PLAD were explored by binary logistic regression analysis.The predictive value of risk factors model for MACE in patients with ICS-PLAD was evaluated by receiver operator curves (ROC).Results Compared with No MACE group,the MACE group had more patients with diabetes(DM),hypertension and number of stenotic vessels ≥ 2,had higher body mass index (BMI),low density lipoprotein cholesterol(LDL-C)and triglycerides(TG) (P all ＜ 0.05).Binary logistic regression analysis showed that the independent risk facts were TG (OR =2.447,P =0.000,95％ CI:1.608-3.725),LDL-C (OR =1.971,P =0.006,95 ％ CI:1.219-3.187) and number of stenotic vessels ≥ 2 (OR =6.596,P =0.000,95 ％ CI:2.995-14.526).The area under the ROC (AUG) of risk factor model for the prediction of MACE in patients with ICS-PLAD were 0.794 (P =0.000).Conclusion Patients with ICS-PLAD,with DM,hypertension,number of stenotic vessels ≥2,obesity,high LDL-C or high TG,had higher MACE rate.TG,LDL-C and number of stenotic vessels ≥2 were the independent risk factors of MACE in patients with ICS-PLAD.The risk factors model has some clinical value for the prediction of MACE in patients with ICS-PLAD.
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Objective To explore the potential relationship between left coronary bifurcation angle and plaques forming in left anterior descending artery by dual-source CT angiography.Methods One hundred patients who underwent dual-source CT angiography in our hospital from January to May during 2016 and had plaques in left anterior descending artery were retrospectively studied,while 100 patients with normal image were as negative controls.There were 57 male and 43 female at the mean age of (57.54 ±-8.38) years in negative controls,and 64 male and 36 female at the mean age of (62.08 ± 13.94) years in patients with left anterior descending artery plaques.The left coronary bifurcation angle was measured by multi-planar reconstruction (MPR) and maximum density projection (MIP) techniques.Results The left coronary bifurcation angle in negative control group were range from 41.25°to 112.14°,at the mean age of 69.45 ° ± 18.71 °,while range from 54.14 ° to 128.12 o,at the mean age of 85.65 °-± 15.96 ° in plaque group.The bifurcation angle in plaque group was larger than those in negative control group(P ＜ 0.05).Conclusion Dual-source CTA could objectively evaluate left coronary bifurcation angle and plaque character.The left coronary bifurcation angle had an important influence on the formation of left anterior descending artery plaque.
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Objective To systematically review the efficacy and safety of drug-eluting stent(DES) versus coronary artery bypass grafting(CABG) in the treatment of left anterior descending coronary artery(CAD) stenosis.Methods Literature about the efficacy and safety of DES versus CABG for LAD stenosis was retrieved from digital databases of MEDLINE, EMbase, PubMed, and the Cochrane Library by November 2016.Data extraction and quality assessment of included studies were conducted by two independent reviewers.RevMan 5.3 software was used to perform meta-analysis.Results Ten studies involving 9771 patients were finally included.The results of meta-analysis showed that there was no significant difference in mortality [RR=0.88,95%CI(0.70,1.11),P=0.28],major adverse cardiovascular events[MACE,RR=1.04,95%CI(0.88,1.24),P=0.63] or myocardial infarction [MI,RR=0.92,95%CI(0.56,1.53),P=0.75], but PCI-DES significantly increased the risk of TVR [OR=2.43,95%CI(1.61,3.69),P<0.0001].Conclusion For LAD stenosis, PCI-DES strategy causes as high a rate of mortality, MACE and MI as CABG or DES, but PCI-DES can significantly increase the risk of TVR, so we should be cautious clinically.
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AIM OF STUDY: Breast conserving surgery (BCS) is the standard treatment for stage I and II breast cancer. Multiple studies have shown that recurrences after lumpectomy occur mainly in or near the tumor bed. Use of accelerated partial breast irradiation (APBI) allows for significant reduction in the overall treatment time that results in increasing patient compliance and decreasing healthcare costs. We conducted a treatment planning study to evaluate the role of intensity modulated radiation therapy (IMRT) with regards to three‑dimensional conformal radiation therapy (3DCRT) in APBI. MATERIALS AND METHODS: Computed tomography planning data sets of 33 patients (20 right sided and 13 left sided) with tumor size less than 3 cm and negative axillary lymph nodes were used for our study. Tumor location was upper outer, upper inner, central, lower inner, and lower outer quadrants in 10, 10, 5, 4 and 4 patients, respectively. Multiple 3DCRT and IMRT plans were created for each patient. Total dose of 38.5 Gy in 10 fractions were planned. Dosimetric analysis was done for the best 3DCRT and IMRT plans. RESULTS: The target coverage has been achieved by both the methods but IMRT provided better coverage (P = 0.04) with improved conformity index (P = 0.01). Maximum doses were well controlled in IMRT to below 108% (P < 0.01). Heart V2 Gy (P < 0.01), lung V5 Gy (P = 0.01), lung V10 Gy (P = 0.02), contralateral breast V1 Gy (P < 0.01), contralateral lung V2 Gy (P < 0.01), and ipsilateral uninvolved breast (P < 0.01) doses were higher with 3DCRT compared to IMRT. CONCLUSION: Dosimetrically, IMRT–APBI provided best target coverage with less dose to normal tissues compared with 3DCRT‑APBI.
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Objective The purpose of this study was to compare two types of myocardial infarction ( MI) models in Beagle dogs. Methods 30 dogs were divided randomly into three groups ( n =10 ) . ① The sham?operated group underwent pericardiotomy but without coronary artery ligation. The other two model groups were made under video?assisted thoracoscopy ( VATS) , where the left anterior descending coronary artery was closed by titanium clips:②The direct vision group:the minimally invasive closure of the artery was performed under direct vision. In this group, the thoracoscopic operation was performed through a 3?0 cm small incision opened at the margin of the left third rib. ③ The thoracoscopic group:the video?assisted thoracoscope was inserted into the chest through a 1?0 cm exploratory hole in the midline of the third rib, and the surgical instruments were inserted through two 0?5 cm operating holes at the para?sternum line of the third rib and midclavicular line of the fourth rib. Electrocardiogram ( ECG) was recorded and the levels of serum creatine kinase?MB ( CK?MB) and troponin I ( cTnI) were measured after modeling. The heart tissue samples were examined by histology using HE staining. The success rate of model establishment, durations from skin incision to chest closing and the wound healing were recorded. Results Compared with the sham?operated group, changes of myocardial infarction were observed in the two model groups ( ECG S?T segment elevation, increased serum CK?MB and cTnI levels, myocardial ischemia and fibrosis, and reduced amount of cardiomyocytes ) . The survival rate was 90% in both of the two model groups. The operating time was shorter in the minimally invasive surgery under direct vision group, and the wound healing time was shorter in the thoracoscopic group. Conclusions The myocardial infarction models generated by minimally invasive surgery have less trauma and low mortality in the dogs. This model is suitable for investigation of pathophysiological mechanism associated with myocardial infarction.
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Introduction: The segment of epicardial coronary artery that traverses intramurally through the myocardium and bridged by a bunch of cardiac muscle fibers is called tunneled artery or intramural artery. The band of cardiac muscle fibers passing over the tunneled artery segment is named as myocardial bridge. During angiography milking effect is observed during systole due to the external pressure of muscle fibers on the tunneled artery that leads to narrowing of vessel lumen and further ischemia. Materials & Methods: It is a prospective study performed from 2012- 2015 in cardiac centers available around Tirupati, Andhra Pradesh, South India. A total number of 2015 adult patients who underwent diagnostic coronary angiography were evaluated to detect myocardial bridges. With the informed consent the relevant data was collected from the patients and analyzed. Results: The prevalence of myocardial bridges was 3.17%. Among the 2015 patients 70.7% are males and 29.2% are females. Among 64 myocardial bridge positive cases 62.5% were male and 37.5% were female patients. Regarding coronary dominance 84% were right dominant and 14.4% were left dominant and 1.6% are balanced. The percentage incidence of myocardial bridging according to dominance was 3.01% for right dominant patients, 4.12% for left dominant patients and 3.1% for balanced dominant patients. In all the myocardial bridge positive cases they were located on the left anterior descending artery (LAD). According to diagnosis the patients with normal coronaries were 22.6%, patients with MILD CAD were 17.9%, patients with single vessel disease were 23.4%, patients with two vessel disease were 14.7% and the patients with triple vessel disease were 21.3%. The 64 myocardial bridging cases were grouped in to three groups according to their age. Incidence of double bridges was observed in 3 cases of which 66.7% males & 33.3% in females. Conclusion: These results shows that Andhra Pradesh population are with high angiographic incidence of myocardial bridges (MB’s), when compared with other population in India. We observed more lengthy bridges which may cause luminal reduction of coronary vessel and myocardial ischemia (MI), we also observed higher incidence of MB’s in male patients but systolic luminal reduction is more in female patients then in males. These observations suggest that the risk of MI will be more for the female patients with MB’s.
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Introduction: Myocardial bridging is the term used when a segment of major epicardial coronary artery runs intramuscularly under the tunnel formed by fibers of myocardium that bridges instead of it’s normal or routine epicardial path. In the literature there are varying reports on clinical implications of myocardial bridges from protection against atherosclerosis to myocardial ischemia, as well as leading to infarction and sudden cardiac death. Materials and Methods: 150 adult formalin fixed human hearts which were available in the department of Anatomy and Forensic Medicine, S.V.Medical College, Tirupati, Andhra Pradesh, India. These hearts were dissected and observed for the presence, location, type, number and direction of myocardial bridges and their association with coronary dominance. With the help of digital calipers morphometric parameters (length, width& thickness) of myocardial bridges and length of blood vessel underneath the myocardial bridge were measured, noted and photographs were taken. Results: The overall incidence of myocardial bridges was 20.6%( 31/150). Among these 18.6% (28/31) were on left anterior descending (LAD) artery and 2% (03/31) were on posterior interventricular (PIV) artery. The direction of muscle fibers in the bridges were oblique to the direction of the coronary vessels in majority of cases. Length, width and thickness of myocardial bridges were in the range of 12-69.7mm, 3.74-8.6mm and 1.3-3.87mm respectively. Conclusions: Myocardial bridges may be associated with wide range of clinical problems. Contraction of myocardial bridge may results in vascular compression and myocardial ischemia. Knowledge on morphology and morphometric details of myocardial bridges facilitates cardiologists in diagnosis, planning therapeutic strategies and prognostic predictions.