Stenting Of Left Anterior Descending Artery Research Articles

The influence of epicardial resistance on Microvascular Resistance Reserve (MRR)

Abstract Background The optimal index of microvascular function should be specific for the microvascular compartment. Yet, coronary flow reserve (CFR), despite being widely used to diagnose coronary microvascular dysfunction (CMD), is influenced by both epicardial and microvascular resistance. Conversely, microvascular resistance reserve (MRR) adjusts for fractional flow reserve (FFR), and thus is theoretically independent of epicardial resistance. Purpose We tested the hypothesis that MRR, unlike CFR, is not influenced by increasing epicardial resistance, and thus is a more specific index of microvascular function. Methods In a cohort of 16 patients that had undergone proximal left anterior descending artery stenting, we created four grades of artificial stenosis (no stenosis, mild, moderate, and severe) using a coronary angioplasty balloon inflated to different degrees within the stent. For each stenosis grade, we calculated CFR and MRR using continuous thermodilution (64 measurements of each) in order to assess their response to changing epicardial resistance. Results Graded balloon inflation resulted in a significant sequential decrease in mean FFR (no stenosis: 0.82 ±0.05; mild: 0.72 ±0.04; moderate: 0.61 ±0.05; severe: 0.48 ±0.09, p<0.001). This translated into a linear decrease in mean hyperaemic coronary flow (no stenosis: 170.5 ±66.8 ml/min; mild: 149.8 ±58.8 ml/min; moderate: 124.4 ±53.0 ml/min; severe: 94.0 ±45.2 ml/min, p<0.001) (Figure 1). CFR exhibited a marked linear decrease with increasing stenosis (no stenosis: 2.5 ±0.9; mild: 2.2 ±0.8; moderate: 1.8 ±0.7; severe: 1.4 ±0.6), corresponding to a decrease of 0.3 for a decrease in FFR of 0.1 (p<0.001). Conversely, MRR exhibited a minimal decrease across all stenosis grades (no stenosis: 3.0 ±1.0; mild: 3.0 ±1.0; moderate: 2.9 ±1.0; severe: 2.8 ±1.0), corresponding to a decrease of just 0.05 for a decrease in FFR of 0.1 (p<0.001) (Figure 1). Conclusion MRR, unlike CFR, is minimally influenced by epicardial resistance, and thus should be considered the most specific index of microvascular function.Figure 1.Absolute blood flow (Q) vs FFRFigure 2.MRR/CFR vs FFR

The Influence of Epicardial Resistance on Microvascular Resistance Reserve

BackgroundThe optimal index of microvascular function should be specific for the microvascular compartment. Yet, coronary flow reserve (CFR), despite being widely used to diagnose coronary microvascular dysfunction (CMD), is influenced by both epicardial and microvascular resistance. Conversely, microvascular resistance reserve (MRR) adjusts for fractional flow reserve (FFR), and thus is theoretically independent of epicardial resistance. ObjectivesThe authors tested the hypothesis that MRR, unlike CFR, is not influenced by increasing epicardial resistance, and thus is a more specific index of microvascular function. MethodsIn a cohort of 16 patients who had undergone proximal left anterior descending artery stenting, we created 4 grades of artificial stenosis (no stenosis, mild, moderate, and severe) using a coronary angioplasty balloon inflated to different degrees within the stent. For each stenosis grade, we calculated CFR and MRR using continuous thermodilution (64 measurements of each) to assess their response to changing epicardial resistance. ResultsGraded balloon inflation resulted in a significant sequential decrease in mean FFR (no stenosis: 0.82 ± 0.05; mild: 0.72 ± 0.04; moderate: 0.61 ± 0.05; severe: 0.48 ± 0.09; P < 0.001). This translated into a linear decrease in mean hyperemic coronary flow (no stenosis: 170.5 ± 66.8 mL/min; mild: 149.8 ± 58.8 mL/min; moderate: 124.4 ± 53.0 mL/min; severe: 94.0 ± 45.2 mL/min; P < 0.001). CFR exhibited a marked linear decrease with increasing stenosis (no stenosis: 2.5 ± 0.9; mild: 2.2 ± 0.8; moderate: 1.8 ± 0.7; severe: 1.4 ± 0.6), corresponding to a decrease of 0.3 for a decrease in FFR of 0.1 (P < 0.001). In contrast, MRR exhibited a negligible decrease across all stenosis grades (no stenosis: 3.0 ± 1.0; mild: 3.0 ± 1.0; moderate: 2.9 ± 1.0; severe: 2.8 ± 1.0), corresponding to a decrease of just 0.05 for a decrease in FFR of 0.1 (P < 0.001). ConclusionsMRR, unlike CFR, is minimally influenced by epicardial resistance, and thus should be considered the more specific index of microvascular function. This suggests that MRR can also reliably evaluate microvascular function in patients with significant epicardial disease.

Spontaneous resolution of new coronary artery aneurysm following guideline-directed medical therapy after drug-eluting stent implantation

Here, we present a case of a 56-year-old man with acute myocardial infarction. The patient underwent percutaneous coronary intervention (PCI) at the left main bifurcation and mid-left anterior descending artery using drugeluting stents. Four months after the PCI, the patient was readmitted for cardiac arrest. Coronary angiography (CAG) revealed stent thrombosis in the left main-toproximal left anterior descending artery and in-stent restenosis in the left main-toproximal left circumflex artery. We performed balloon angioplasty at the left main to mid-left anterior descending artery and left main to proximal left circumflex artery stents; subsequently, blood flow was fully restored. However, contrast agent extravasation was observed outside the mid-portion of the left main artery to the proximal left anterior descending artery stent, indicating the presence of a coronary artery aneurysm (CAA) outside the stent. After guideline-directed medical therapy with dual antiplatelet agents and high-intensity statins, follow-up CAG revealed near-resolution of the CAA, absence of stenotic lesions, and good blood flow.

Predictors of LV Recovery after Proximal Left Anterior Descending Artery Stenting

Predictors of LV Recovery after Proximal Left Anterior Descending Artery Stenting

Hybrid revascularization: stenting of left internal carotid artery after restenosis, combined with left anterior descending artery stenting and right carotid endarterectomy

We present a description of internal carotid artery restenosis five years after eversion carotid endarterectomy, progression of contralateral internal carotid artery stenosis and coronary atherosclerosis with imaging of haemodynamically significant stenosis of the anterior descending artery. The efficacy of hybrid revascularization is demonstrated: carotid angioplasty with stenting of the left internal carotid artery stenosis + percutaneous coronary intervention for the anterior descending artery + left carotid endarterectomy. We explain the choice of these types of reconstruction and staging of the intervention. We make a conclusion regarding the effectiveness and safety of the implemented treatment strategy.

“Clots and Failures” A Case of COVID-19 Causing STEMI and Persistent Cardiogenic Shock Ultimately Requiring LVAD

IntroductionWe present a case of COVID-19 causing hypercoagulability and inflammatory stress leading to STEMI in a patient who went on to develop persistent cardiogenic shock requiring LVA) implantation.Case Report57-year-old lady developed COVID-19 infection in May 2020. In June 2020, she presented with chest pain, was noted to have STEMI on EKG, complicated by cardiac arrest with ROSC in 14 minutes. She was in cardiogenic shock as well and was started on veno-arterial ECMO. She underwent left anterior descending artery stent placement. Further hospitalization was complicated by persistent cardiogenic shock and complete heart block and underwent pacemaker and cardiac-defibrillator implantation. She developed pulmonary edema, acute kidney injury requiring hemodialysis, shock liver, and persistent cardiogenic shock. She was weaned off VA-ECMO after 4 days but continued to have severely reduced cardiac function. RHC revealed severe volume overload, pulmonary venous hypertension, low cardiac output, and right heart dysfunction. Echo showed severe LV dysfunction with an EF of 15%. A femoral intra-aortic balloon pump(IABP) was placed on July 7, 2020. An attempt was made to wean her off of IABP on July 10th,however, it was unsuccessful and she was transitioned to axillary intra-aortic balloon pump. She remained IABP dependent thereafter and on July 15th, given persistent cardiogenic shock, decision was made to pursue advanced heart failure therapies. After multi-disciplinary discussion, the decision to pursue LVAD implantation was made. She underwent a successful LVAD implantation on July 20th . She failed an extubation trial and underwent tracheostomy on July 23rd . Post LVAD, she developed atrial fibrillation and was started on digoxin and amiodarone. Her symptoms improved and she was subsequently discharged to rehabilitation in late August on amiodarone, digoxin, metoprolol, prasugrel, warfarin, spironolactone and lisinopril. The detailed timeline is shown in figure 1.SummaryHypercoagulability and severe inflammatory stress leading to life-threatening illness is a significant complication of COVID-19 infection. A low threshold for suspecting and treating hypercoagulability and inflammatory induced myocardial ischemia and injury and cardiogenic shock is a reasonable strategy to decrease acute as well as chronic morbidity and mortality.

Cardiac arrest, chronic total occlusion, and occluded stent in a 16-year-old boy with Kawasaki disease: a case report.

BackgroundKawasaki disease is the leading cause of premature coronary artery disease in developed countries. As such, patients may require revascularisation as children. However, there are no randomized data guiding treatment so this must be individualized. This case report describes the decision-making in a young patient requiring revascularization who had already suffered stent occlusion.Case summaryOur patient, a 16-year-old boy with Kawasaki disease, presented with cardiac arrest during exercise. Coronary angiography showed that a proximal left anterior descending artery stent implanted at the age of 8 years had occluded some time ago and his right coronary artery was also chronically occluded. He has discussed in several Heart Team meetings and with international colleagues and a consensus reached to revascularize him surgically.DiscussionIt is vital that young patients with complex coronary disease are discussed in an extensive multidisciplinary setting to determine the most suitable means of treatment. The previously occluded stent was crucial in the individualized decision-making in this patient.

Coronary Sinus Filling Time as a Predictor of Coronary Microvascular Obstruction and Future Cardiovascular Events after Elective Left Anterior Descending Artery Stenting

Abstract Objective The main objective of this article is to study the usefulness of coronary sinus filling time (CSFT) as a predictor of coronary microvascular obstruction (CMVO) and future cardiovascular (CV) events after percutaneous coronary intervention (PCI) for left anterior descending (LAD) in stable coronary artery disease patients. Materials and Methods We analyzed 50 patients with stable angina who underwent elective PCI for single LAD significant stenosis. After stent deployment, coronary sinus was visualized in left anterior oblique 40 degree cranial 30 degree views, CSFT, and corrected thrombolysis in myocardial infarction frame count (cTFC) calculated from frame count. Post-procedure electrocardiographic changes noted and cardiac biomarker creatine phosphokinase and creatine phosphokinase-myocardial band levels estimated, and follow-up was done for 6 months. Patients classified into two groups: Group 1 with major adverse cardiac events (MACE) and Group 2 (without MACE). CSFT and cTFC measurements were compared among the two groups. Results Out of 50 patients who were recruited in the study, Group 1 comprises 20 patients, and Group 2 comprises 30 patients. Among the Group 1, 40% were females, while in Group 2, they were 16%. Group 1 showed high CSFT values compared to Group 2, and such are post-procedure ST, T changes (90% in Group 1, 20% in Group 2), cardiac biomarkers elevation (80% in Group 1, 23.3% in Group 2). At 6 months follow-up ejection fraction was lower in Group 1 (31.8 ± 6.4%) compared with Group 2 (58.8 ± 5.8%) at p &lt; 0.0001, and angina (85%) versus (20%). Mean CSFT was significantly more in Group 1 (5.77 ±0.75s) compared with Group 2 (4.61 ± 0.55s) at p &lt; 0.0001. With respect to cTFC, no significant differences were seen between the two groups (p &lt; 0.5628). Receiver operating characteristic curve analysis showed CSFT of &gt; 5.2s was the best cutoff value to differentiate the two groups. Conclusion CSFT significantly prolonged in patients with adverse cardiac events, and it may be used as a simple and quantitative predictor of CMVO and future CV events after elective PCI.

GLP-1 Is a Coronary Artery Vasodilator in Humans.

BackgroundThe mechanism underlying the beneficial cardiovascular effects of the incretin GLP‐1 (glucagon‐like peptide 1) and its analogues in humans is elusive. We hypothesized that activating receptors located on vascular smooth muscle cells to induce either peripheral or coronary vasodilatation mediates the cardiovascular effect of GLP‐1.Methods and ResultsTen stable patients with angina awaiting left anterior descending artery stenting underwent forearm blood flow measurement using forearm plethysmography and post–percutaneous coronary intervention coronary blood flow measurement using a pressure‐flow wire before and after peripheral GLP‐1 administration. Coronary sinus and artery bloods were sampled for GLP‐1 levels. A further 11 control patients received saline rather than GLP‐1 in the coronary blood flow protocol. GLP‐1 receptor (GLP‐1R) expression was assessed by immunohistochemistry using a specific GLP‐1R monoclonal antibody in human tissue to inform the physiological studies. There was no effect of GLP‐1 on absolute forearm blood flow or forearm blood flow ratio after GLP‐1, systemic hemodynamics were not affected, and no binding of GLP‐1R monoclonal antibody was detected in vascular tissue. GLP‐1 reduced resting coronary transit time (mean [SD], 0.87 [0.39] versus 0.63 [0.27] seconds; P=0.02) and basal microcirculatory resistance (mean [SD], 76.3 [37.9] versus 55.4 [30.4] mm Hg/s; P=0.02), whereas in controls, there was an increase in transit time (mean [SD], 0.48 [0.24] versus 0.83 [0.41] seconds; P<0.001) and basal microcirculatory resistance (mean [SD], 45.9 [34.7] versus 66.7 [37.2] mm Hg/s; P=0.02). GLP‐1R monoclonal antibody binding was confirmed in ventricular tissue but not in vascular tissue, and transmyocardial GLP‐1 extraction was observed.Conclusions GLP‐1 causes coronary microvascular dilation and increased flow but does not influence peripheral tone. GLP‐1R immunohistochemistry suggests that GLP‐1 coronary vasodilatation is indirectly mediated by ventricular‐coronary cross talk.

Mending the broken stent

A 54-year-old male patient diabetic with history of coronary angioplasty 4 years back with a drug eluting stent presented with anterior wall ST segment Elevation Myocardial Infarction. He was taken up for primary angioplasty, diagnostic angiogram showed 100% thrombotic occlusion of proximal left anterior descending artery with an aneurysm. A stent boost was done which showed a fragmented left anterior descending artery stent with disarticulation of both fragments. Two drug eluting stents one in proximal left anterior descending artery bridging the broken fragments of the previous stent and other in a mid left anterior descending artery lesion of 90% were deployed with excellent angiographic outcome with TIMI III flow.

TCTAP C-110 Left Anterior Descending Artery Stenting with Stent Dislodgement in Left Main-Retrieved

### Patient initials or identifier number KK ### Relevant clinical history and physical exam Recent AWMI, Not thrombolysed AOE NYHA Class III ### Relevant test results prior to catheterization Echo:LVEF 55% ### Relevant catheterization findings OM1 and OM2 shows plaque LAD cut off after

Differences of side branch jailing between left main-left anterior descending artery stenting and left main-left circumflex artery stenting with Nobori biolimus-eluting stent.

The aim of this study is to indicate differences of side branch jailing between the left main (LM)-left anterior descending artery (LAD) stenting and the LM-left circumflex artery (LCx) stenting. Thirty-one patients who underwent single-stenting using a two-link ten-crowns biolimus-eluting stent (Japanese design of BES, J-BES) and subsequent kissing balloon dilation (KBD) on an LM bifurcation with optical coherence tomography (OCT) were divided into two groups according to the stented vessel. Bifurcation angles were measured by three-dimensional (3D) quantitative coronary analysis. The jailing pattern on a side branch ostium was evaluated by stent-enhanced 3D-OCT. Incomplete stent apposition (ISA) after KBD was compared between the stented vessels. The to-be-stented angle of the LM-LCx stenting (n=11) was significantly steeper than that of the LM-LAD stenting (n=20) (132.6°±16.9° vs. 150.7°±10.6°, p<0.01). The incidence of the free carina type, which has no stent links bridging from a carina, in the LM-LCx stenting was significantly higher than that in the LM-LAD stenting (90.9 vs. 45.0%, p=0.02). The percentage of ISA at the bifurcation segment in the LM-LCx stenting was significantly smaller than that in the LM-LAD stenting (4.4±8.2 vs. 12.7±9.2%, p=0.0003). This study showed, by higher incidence of the favorable configuration, that the LM-LCx stenting achieved a smaller percentage of ISA than the LM-LAD stenting. These insights may help guide LM bifurcation stenting with J-BES.

New polyurethane covered stent with low profile for treatment of a large aneurysm after Left Anterior Descending artery stenting: First experience

New polyurethane covered stent with low profile for treatment of a large aneurysm after Left Anterior Descending artery stenting: First experience

TCTAP C-043 Is It Dissection or Plaque Migration Proximally Following Left Anterior Descending Artery Stenting?

### Patient initials or identifier number MAN 14 ### Relevant clinical history and physical exam 62 year old male Known to have poorly controlled Type II Diabetes Mellitus and Hypertension. He was on oral hypoglycemic agents and angiotensin receptor blockers irregularly Quit smoking 6 months

Impact of Myocardial Bridge on Clinical Outcome After Coronary Stent Placement

Most intravascular ultrasound (IVUS)-identifiable myocardial bridges (MBs) were not appreciated angiographically, especially when they occurred adjacent to fixed proximal obstructive disease. The impact of MB stent placement on clinical outcome was determined in 317 consecutive patients with obstructive left anterior descending coronary artery lesions undergoing coronary stent placement. In these patients, IVUS identified 70 MBs, defined as a segment of coronary artery with both systolic compression and perivascular echolucent muscle. IVUS showed that the stent extended into the MB segment beyond the obstructive lesion in 24 patients (34%; MB stent group), although significant plaque was not observed within any MB segment. In the remaining 46 patients, the left anterior descending artery stent was implanted in only the obstructive lesion, avoiding the distal MB segment (non-MB stent group). Minimum stent area was significantly smaller in the MB stent group than non-MB stent group (4.8 +/- 1.1 vs 5.8 +/- 1.8 mm(2); p = 0.02). Rates of target-lesion revascularization, target-vessel revascularization, and composite end point (death/myocardial infarction/target-lesion revascularization/target-vessel revascularization, evaluated at a mean follow-up of 358 +/- 252 days) were more common in patients with versus without MB stent placement. Specifically, target-lesion revascularization rates were 24% versus 3%, respectively (log-rank p = 0.003). In-stent restenosis occurred within the stented MB segment in 3 of 5 MB stent group patients who required target-lesion revascularization (60%). In conclusion, inadvertent MB stent placement in left anterior descending artery lesions occurred commonly and may have been associated with an increased incidence of late events.

Drug-Eluting Stent Thrombosis: Results From the Multicenter Spanish Registry ESTROFA (Estudio ESpañol sobre TROmbosis de stents FArmacoactivos)

This study sought to assess the incidence, predictors, and outcome of drug-eluting stent(DES) thrombosis in real-world clinical practice. The DES thromboses in randomized trials could not be comparable to those observed in clinical practice, frequently including off-label indications. We designed a large-scale, nonindustry-linked multicentered registry, with 20 centers in Spain. The participant centers provided follow-up data for their patients treated with DES, reporting a detailed standardized form in the event of any angiography-documented DES-associated thrombosis occurring. Of 23,500 patients treated with DES, definite stent thrombosis(ST) developed in 301: 24 acute, 125 subacute, and 152 late. Of the late, 62 occurred >1 year(very late ST). The cumulative incidence was 2% at 3 years. Antiplatelet treatment had been discontinued in 95 cases(31.6%). No differences in incidences were found among stent types. Independent predictors for subacute ST analyzed in a subgroup of 14,120 cases were diabetes, renal failure, acute coronary syndrome, ST-segment elevation myocardial infarction, stent length, and left anterior descending artery stenting, and for late ST were ST-segment elevation myocardial infarction, stenting in left anterior descending artery, and stent length. Mortality at 1-year follow-up was 16% and ST recurrence 4.6%. Older age, left ventricular ejection fraction <45%, nonrestoration of Thrombolysis In Myocardial Infarction flow grade 3, and additional stenting were independent predictors for mortality. The cumulative incidence of ST after DES implantation was 2% at 3 years. No differences were found among stent types. Patient profiles differed between early and late ST. Short-term prognosis is poor, especially when restoration of normal flow fails.

Three‐dimensional modeling of double‐stent techniques at the left main coronary artery bifurcation using micro‐focus X‐ray computed tomography

Various double-stent techniques using drug-eluting stents have been proposed to treat the left main coronary artery (LMCA) bifurcation. However, use of these techniques is frequently associated with focal restenosis at the ostium of the left circumflex coronary artery (LCX). To examine the results of double-stent techniques, using a silicon model of the LMCA bifurcation and three-dimensional (3D) reconstruction images created with micro-focus X-ray computed tomography (MFCT). Crush, kissing, and modified T stentings were performed with bare metal stents in a LMCA bifurcation model. The stents were then inspected using MFCT at a minimal resolution of 0.06 mm. Gaps in stent apposition to the vessel were observed at the site of stent overlap in the distal LMCA with all stenting techniques. In crush stenting, when the left anterior descending artery stent overlapped the LCX stent, the latter was crushed on the myocardial side of the vessel, and a gap was observed on the nonmyocardial side, at the LCX ostium. When the overlap was reversed, the LCX stent was crushed on the nonmyocardial side and a gap was observed on the myocardial side. In the case of kissing stents, stent overlap created a gap beneath the overlapped portion of the stents. In modified T-stenting, correct positioning of the LCX stent was difficult and MFCT imaging revealed a nonmyocardial gap. Close apposition of the stent to the vessel at the ostium of the LCX is difficult to achieve at the LMCA bifurcation, regardless of which double-stent technique is employed, due to the site's wide bifurcation angle and complex 3D structure. The distribution of plaque and the bifurcation angle should be considered before double-stent deployment, to avoid leaving a gap over significant plaques.

Refraction correction in beam tracking speed of sound estimations using multiple tracking transducers

This study sought to assess the incidence, predictors, and outcome of drug-eluting stent (DES) thrombosis in real-world clinical practice.The DES thromboses in randomized trials could not be comparable to those observed in clinical practice, frequently including off-label indications.We designed a large-scale, nonindustry-linked multicentered registry, with 20 centers in Spain. The participant centers provided follow-up data for their patients treated with DES, reporting a detailed standardized form in the event of any angiography-documented DES-associated thrombosis occurring.Of 23,500 patients treated with DES, definite stent thrombosis (ST) developed in 301: 24 acute, 125 subacute, and 152 late. Of the late, 62 occurred >1 year (very late ST). The cumulative incidence was 2% at 3 years. Antiplatelet treatment had been discontinued in 95 cases (31.6%). No differences in incidences were found among stent types. Independent predictors for subacute ST analyzed in a subgroup of 14,120 cases were diabetes, renal failure, acute coronary syndrome, ST-segment elevation myocardial infarction, stent length, and left anterior descending artery stenting, and for late ST were ST-segment elevation myocardial infarction, stenting in left anterior descending artery, and stent length. Mortality at 1-year follow-up was 16% and ST recurrence 4.6%. Older age, left ventricular ejection fraction <45%, nonrestoration of Thrombolysis In Myocardial Infarction flow grade 3, and additional stenting were independent predictors for mortality.The cumulative incidence of ST after DES implantation was 2% at 3 years. No differences were found among stent types. Patient profiles differed between early and late ST. Short-term prognosis is poor, especially when restoration of normal flow fails.