Accuracy of global longitudinal and territorial longitudinal strain in determining myocardial viability in out of window period Anterior wall myocardial infarction patients

Funding Acknowledgements

Type of funding sources: None.

Background

Primary percutaneous intervention remains the principal treatment modality for anterior wall myocardial infarction (AWMI). However, a large fraction of patients especially in the developing countries present outside the window period (OWP) with no chest pain and akinetic left anterior descending (LAD) territory on echocardiography. Revascularization in these patients is primarily guided by viability status.

Purpose

This study was conducted to determine the accuracy of strain echocardiographic parameters compared to single-photon emission computed tomography (SPECT) in predicting myocardial viability in patients of AWMI presenting OWP.

Methods

All patients presenting with AWMI-OWP without ongoing chest pain and akinetic LAD territory on echocardiography from December 2020 to June 2021 were recruited. All patients underwent determination of both Global longitudinal strain (GLS) and territorial longitudinal strain (TLS) within 24-72 hours on AWMI. In addition, all underwent SPECT to determine the percentage of non-viable myocardium. On SPECT, a defect >5% myocardial territory showing severe reperfusion defect was considered as a marker of non-viability. 

Results

A total of 27 patients were recruited. The mean age of the population was 61.66 + 12.6 years. Acute left ventricular failure (LVF) and cardiogenic shock (CS) was present in 6 (22.2%) and 5 (18.5%) patients respectively. Out of 22 patients who underwent angiography, majority of the patients 19 (86%) had single vessel disease involving the LAD.

The mean left ventricular ejection fraction (LVEF) of the study group was 29.6 + 6.5%. The mean GLS and LAD territory TLS of the study group was -11.13 + 3.14% and -7.2 + 2.75% respectively. On SPECT, 8 (29.6%) patients had non-viable underlying myocardium.

Parameters that very significantly associated with non-viability on SPECT included past history of CAD (p = 0.004), smoking (p = 0.05) and presentation with LVF (p = 0.0008) and CS (p = 0.001).

The mean LVEF was significantly lower in the group with non-viability on SPECT (32.3 + 5.1% vs 23.1 + 4.5%; p < 0.001). Both GLS (-12.8 + 1.4% vs -7.1+ 2.3%; p < 0.001) and TLS (-8.7 + 1.4% vs -3.8 + 1.8%; p < 0.001) were significantly lower in group showing non-viability on SPECT.

On receiver operating curves, a GLS of > -10.45% and TLS of > -6.65%, both had a sensitivity of 87.5% and specificity of 89.5% in predicting non-viability on SPECT. Both showed good accuracy in predicting non-viability on overall quality model. (Figures 1 and 2)

Conclusion

Modalities like cardiac magnetic resonance, SPECT or positron emission tomography are resource dependent and take time to be performed. Hence, performing these investigations is challenging in unstable patients. Strain echocardiography provides GLS of the myocardium which has good sensitivity and specificity in predicting viability and can be performed safely and quickly in this high-risk group. Abstract Figure.  Abstract Figure. Overall quality model

Angiographic Profiles in Persistent Non-Valvular Atrial Fibrillation Patients

Funding Acknowledgements

Type of funding sources: None.

OnBehalf

Cardiology dept. PGIMER, Chandigarh

Background

The relationship of atrial fibrillation (AF) with coronary artery disease (CAD) is well established. Atrial ischemia due to obstructive CAD has been identified as one of the key risk factors, leading to AF. However, sufficient evidence exists as to the presence of myocardial ischemia on stress imaging, even without the presence of obstructive CAD in AF patients. Slow flow and coronary tortuosity on angiogram can lead to downstream myocardial ischemia independent of CAD. 

Purpose

We aimed to delineate the angiographic profiles in AF patients with attention to slow flow and tortuosity leading to ischemia in those without obstructive CAD. 

Methods

The study was a nonrandomised, prospective, single-centre observational study of consecutive patients of persistent non valvular AF. Symptomatic patients despite optimal medical therapy (OMT) for 3 months were recruited and all underwent coronary angiograms (CAG). Patients with known CAD or prior history of myocardial infarction were excluded. Further angiographic analysis was done in those without obstructive CAD to determine incidence of slow flow (>27 corrected TIMI frame count) and tortuosity (presence of ≥3 fixed bends in an epicardial artery). 

Results

A total of 70 patients were recruited and followed for a mean duration of 12 ± 1.4 months. The mean age of the study group was 66.07 (±11.49). Hypertension (74%) was the commonest comorbidity followed by obesity (35%) and diabetes (30%). At CAG, 32/70 (46%) had obstructive CAD, 17/70 (24%) had non obstructive (<50-70% stenosis) CAD and 21/70 (30%) had normal coronaries without atherosclerosis. Amongst patients without obstructive CAD (n = 38) slow flow was seen in 16/38 (42%) and coronary tortuosity in 11/38 (29%) patients. There ware no differences in terms of death, HF and FVR hospitalisations or stroke at follow up between the obstructive CAD vs no obstructive CAD. However in patients without obstructive CAD, hospitalisations for FVR was significantly increased in those having slow flow on CAG, 9/12 (75%) vs 7/26 (27%) in those without slow flow (p value = 0.005). The mean TIMI frame count was also significantly higher in those with FVR hospitalisations 35.3 ± 11 vs 25.8 ± 8.9  (p value = 0.005). TIMI frame count >31 had a sensitivity of 83% and a specificity of 69% for predicting hospitalisations for FVR on ROC curve(AUC = 0.71). 

Conclusions

CAD is closely related to AF and majority (70%) of our patients had evidence of atherosclerotic CAD on CAG in our study. A large proportion of patients with no evidence of obstructive CAD on CAG had slow flow or coronary tortuosity. Significantly increased hospitalisation for FVR seen in the slow flow group shows its significance and may lead to newer treatment modalities in future. Further larger studies looking at these aspects on CAG may give further insight as to the nature and prognosis of these entities. Abstract Figure 1: Flow diagram showing the patie

Observational study of Covid-19 patients presenting with acute coronary syndrome at a tertiary care center in India

Aim

Patients with Covid-19 are theoretically at a higher risk of ACS, as respiratory infections can often lead to coronary endothelial damage and plaque rupture. Initial reports during start of pandemic suggested decrease in STEMI patients, however this has been explained by iatrophobia rather than actual decrease. Data on pathophysiology and outcome of patients presenting with ACS is scarce. We did a prospective observational study to study epidemiology and outcomes of Covid-19 patients with ACS.

Methods

A total of 654 patients were admitted with Covid-19 at PGIMER, Chandigarh from August 2020 to February 2021, 35 (5.3%) consecutive patients of ACS were enrolled into the study. Acute myocardial infarction was defined as per fourth universal definition of myocardial infarction. Diagnosis of Covid-19 was established using RT-PCR from nasopharyngeal swab. Angiographic assessment was done by two interventional cardiologists.

Results

Mean age of patients was 59.5±11.8 years, males comprised majority (80%) of study group. Most common risk factor was hypertension seen in around 70% followed by DM in 57% patients. Most common symptom at presentation was rest angina seen >90% while history of fever was present in only 31.4%. STEMI was most common ACS seen in 45.7% followed by USA in 23% patients. CS was present in 15% patients at presentation while another 5% developed shock in hospital. Oxygen requirement was required in over half the patients while 25% patients succumbed to illness in hospital.Thrombolysis was done in half the patients of STEMI. In view of Covid-19 disease 71.4% required dexamethasone and remdesivir. Coronary angiography was done in around 20% patients, which revealed obstructive CAD in 83% patients with 60% patients having 100% occlusion of IRA. Percutaneous intervention was done in 66% patients. Hypoalbuminemia was commonly seen patients with mean albumin of 3.3 gm/dL. Low T3 syndrome was most common thyroid function abnormality seen in 37.1%.On univariate analysis age, BNP levels and albumin were able to predict 30-day mortality.

Conclusion

ACS can be first presentation of patients with Covid-19 as shown by our study only 30% patients had prior history of fever. Our data reaffirms that patients with Covid-19 and ACS have worse prognosis. Interestingly mortality in our study was comparable to western study, despite low rate of angiography and intervention thus underscoring individualization of therapy. We believe Type-2 myocardial infarction is common in pathophysiology of patients who benefit most from medical therapy.

Funding Acknowledgement

Type of funding sources: None.

Angiographic profiles in patients of persistent non-valvular atrial fibrillation from a tertiary care center in north india

Funding Acknowledgements

Type of funding sources: None.

Background

The relationship of atrial fibrillation (AF) with coronary artery disease (CAD) is well established. Atrial ischemia due to obstructive CAD has been identified as one of the key risk factors, leading to AF. However, sufficient evidence exists as to the presence of myocardial ischemia on stress imaging, even without the presence of obstructive CAD in AF patients. Slow flow and coronary tortuosity on angiogram can lead to downstream myocardial ischemia independent of CAD.

Purpose

We aimed to delineate the angiographic profiles in AF patients with attention to slow flow and tortuosity leading to ischemia in those without obstructive CAD.

Methods

The study was a nonrandomised, prospective, single-centre observational study of consecutive patients of persistent non valvular AF. Symptomatic patients despite optimal medical therapy (OMT) for 3 months were recruited and all underwent coronary angiograms (CAG). Patients with known CAD or prior history of myocardial infarction were excluded. Further angiographic analysis was done in those without obstructive CAD to determine incidence of slow flow (>27 corrected TIMI frame count) and tortuosity (presence of ≥3 fixed bends in an epicardial artery).

Results

A total of 70 patients were recruited and followed for a mean duration of 12 ± 1.4 months. The mean age of the study group was 66.07 (±11.49). Hypertension (74%) was the commonest comorbidity followed by obesity (35%) and diabetes (30%). At CAG, 32/70 (45%) had obstructive CAD, 17/70 (24%) had non obstructive (<50-70% stenosis) CAD and 21/70 (30%) had normal coronaries without atherosclerosis. Amongst patients without obstructive CAD (n = 38) slow flow was seen in 16/38 (42%) and coronary tortuosity in 11/38 (29%) patients. There ware no differences in terms of death, HF and FVR hospitalisations or stroke at follow up between the obstructive CAD vs no obstructive CAD. However in patients without obstructive CAD, hospitalisations for FVR was significantly increased in those having slow flow on CAG, 9/12 (75%) vs 7/26 (27%) in those without slow flow (p value = 0.005). The mean TIMI frame count was also significantly higher in those with FVR hospitalisations 35.3 ± 11 vs 25.8 ± 8.9  (p value = 0.005). TIMI frame count >31 had a sensitivity of 83% and a specificity of 69% for predicting hospitalisations for FVR on ROC curve(AUC = 0.71).

Conclusions

CAD is closely related to AF and majority (70%) of our patients had evidence of atherosclerotic CAD on CAG in our study. A large proportion of patients with no evidence of obstructive CAD on CAG had slow flow or coronary tortuosity. Significantly increased hospitalisation for FVR seen in the slow flow group shows its significance and may lead to newer treatment modalities in future. Further larger studies looking at these aspects on CAG may give further insight as to the nature and prognosis of these entities.