Comparison of clinical outcomes between sufficient versus insufficient diagonal branch flow in anterior acute myocardial infarction

Angiographic Coronary Calcification: A Simple Predictor of Long-Term Clinical Outcomes in Patients with Acute Myocardial Infarction

AIMS

Coronary calcification detected by coronary angiography is a simple risk marker for long-term clinical outcomes in stable coronary artery disease. However, the significance of angiographic coronary calcification in the culprit lesion of acute myocardial infarction (AMI) has not been fully discussed. The purpose of this retrospective study was to assess the usefulness of angiographic coronary calcification as a risk marker for long-term clinical outcomes following percutaneous coronary intervention to the culprit lesions of AMI.

METHODS

We included 1209 patients with AMI and divided them into the none-mild calcification group (n=923) and the moderate-severe calcification group (n=286) according to angiographic coronary calcification in the culprit lesion of AMI. The primary endpoint was the occurrence of major adverse cardiac events (MACE), which was defined as a composite of all-cause death, nonfatal MI, readmission for heart failure, and ischemia-driven target vessel revascularization.

RESULTS

The median follow-up duration was 542 (Q1: 182, Q3: 990) days. A total of 345 MACE were observed during the study period. The occurrence of MACE was significantly greater in the moderate-severe calcification group than in the none-mild calcification group (43.4% vs. 23.9%, p＜0.001). In the multivariate Cox hazard model, moderate-severe calcification was significantly associated with MACE (hazard ratio 1.302, 95% confidence interval 1.011-1.677, p=0.041) after controlling multiple confounding factors.

CONCLUSIONS

Angiographically moderate to severe calcification in AMI culprit lesion was associated with long-term worse clinical outcomes. Angiographic coronary calcification can be a simple risk marker in patients after AMI.

Association of Left Ventricular Systolic Function with Diagonal Branch Flow in Patients with First Anterior ST-Elevation Myocardial Infarction Treated with Primary Angioplasty

Background: There are few studies about the impact of diagonal branch blood flow on echocardiographic findings in patients with first acute anterior myocardial infarction undergoing primary angioplasty. Objectives: We aimed to compare left ventricular systolic function measures in patients with first acute anterior ST-segment elevation myocardial infarction (STEMI) treated with primary angioplasty based on diagonal branch blood flow after the procedure. Methods: This study was a single-center study that enrolled patients with their first acute anterior STEMI treated with primary angioplasty in our center between October 2020 and March 2021. Patients were divided into two groups: The patients with final thrombolysis in myocardial infarction (TIMI) flow III in diagonal (sufficient diagonal flow) and patients with final TIMI flow less than III in diagonal (insufficient diagonal flow) after the procedure. The left ventricular Wall-Motion Score Index (WMSI) and left ventricular ejection fraction (LVEF) were compared between the two groups. Results: A total of 107 patients with first anterior STEMI treated with primary PCI were enrolled in the present study, of which 13 patients (12.1%) had insufficient diagonal flow after primary coronary angioplasty. The LVEF was lower in patients with insufficient diagonal flow (32.92 ± 7.29% vs. 39 ± 8.68%, P = 0.018). Also, this group had higher LV WMSI (1.68 ± 0.28 vs. 1.49 ± 0.26, P = 0.029). Conclusions: The present study showed that in patients with first acute anterior STEMI undergoing primary angioplasty, insufficient diagonal branch flow after the procedure was associated with worse left ventricular systolic function and higher LV WMSI.

Association of collateral flow with clinical outcomes in patients with acute myocardial infarction

Coronary collateral flow is an important prognostic marker in percutaneous coronary intervention (PCI) for chronic total occlusion. However, the role of collateral flow to the culprit lesion of acute myocardial infarction (AMI) has not been fully established yet. The purpose of this retrospective study was to examine the association between collateral flow and long-term clinical outcomes in patients with AMI. We included 937 patients with AMI, and divided those into the no-collateral group (n = 704) and the collateral group (n = 233) according to the presence or absence of collateral flow to the culprit lesion of AMI. The primary endpoint was the incidence of major adverse cardiac events (MACE), which was defined as a composite of all-cause death, non-fatal MI, re-admission for heart failure, and ischemia driven target vessel revascularization. The median follow-up duration was 473 days (Q1: 184 days- Q3: 1027 days), and a total of 263 MACE was observed during the study period. The incidence of MACE was significantly greater in the no-collateral group than in the collateral group (29.8% vs. 22.3%, p = 0.027). In the multivariate COX hazard model, the presence of collateral flow was inversely associated with MACE (HR 0.636, 95% CI 0.461-0.878, p = 0.006) after controlling multiple confounding factors. In conclusion, the presence of collateral flow to the culprit lesion of AMI was inversely associated with long-term adverse outcomes. Careful observation of collateral flow may be important in emergent coronary angiography to stratify a high-risk group among various patients with AMI.

Ventricular fibrillation storm after revascularization of chronic total occlusion of the left anterior descending artery: is this reperfusion arrhythmia?

Electrical storm is a life-threatening emergency condition defined as three or more episodes of ventricular tachycardia or ventricular fibrillation (VF) within 24 hours requiring anti-tachycardia therapy, electrical cardioversion, or defibrillation. However, studies of the incidence of electrical storm after chronic total occlusion-percutaneous coronary intervention (CTO-PCI) are limited,⁷ and post-procedural VF after revascularization of CTO has not been described. The purpose of this article was to present a case of post-operative VF electrical storm after revascularization of CTO of the left anterior descending (LAD) artery to determine whether the electrical storm was caused by reperfusion arrhythmia or compromise of either branch vessels or the collateral circulation during intervention.

Modifiable and unmodifiable factors associated with slow flow following rotational atherectomy

Background

Although several groups reported the risk factors for slow flow during rotational atherectomy (RA), they did not clearly distinguish modifiable factors, such as burr-to-artery ratio from unmodifiable ones, such as lesion length. The aim of this retrospective study was to investigate the modifiable and unmodifiable factors that were associated with slow flow.

Methods

We included 513 lesions treated with RA, which were classified into a slow flow group (n = 97) and a non-slow flow group (n = 416) according to the presence or absence of slow flow just after RA. The multivariate logistic regression analysis was performed to find factors associated with slow flow.

Results

Slow flow was inversely associated with reference diameter [Odds ratio (OR) 0.351, 95% confidence interval (CI) 0.205–0.600, p<0.001], primary RA strategy (OR 0.224, 95% CI 0.097–0.513, p<0.001), short single run (≤15 seconds) (OR 0.458, 95% CI 0.271–0.776, p = 0.004), and systolic blood pressure (BP) ≥ 140 mmHg (OR 0.501, 95% CI 0.297–0.843, p = 0.009). Lesion length (every 5 mm increase: OR 1.193, 95% CI 1.093–1.301, p<0.001), angulation (OR 2.054, 95% CI 1.171–3.601, p = 0.012), halfway RA (OR 2.027, 95% CI 1.130–3.635, p = 0.018), initial burr-to-artery ratio (OR 1.451, 95% CI 1.212–1.737, p<0.001), and use of beta blockers (OR 1.894, 95% CI 1.004–3.573, p = 0.049) were significantly associated with slow flow.

Conclusions

Slow flow was positively associated with several unmodifiable factors including lesion length and angulation, and inversely associated with reference diameter. In addition, slow flow was positively associated with several modifiable factors including initial burr-to-artery ratio and use of beta blockers, and inversely associated with primary RA strategy, short single run, and systolic blood pressure just before RA. Application of this information could help to improve RA procedures.

Comparison of the incidence of slow flow after rotational atherectomy with IVUS-crossable versus IVUS-uncrossable calcified lesions

Although the usefulness of intravascular ultrasound (IVUS) in rotational atherectomy (RA) has been widely recognized, an IVUS catheter may not cross the target lesion because of severe calcification. The aim of this study was to compare the incidence of slow flow following RA between IVUS-crossable versus IVUS-uncrossable calcified lesions. We included 284 RA lesions, and divided into an IVUS-crossable group (n = 150) and an IVUS-uncrossable group (n = 134). The primary endpoint was slow flow just after RA. The incidence of slow flow (TIMI flow grade ≤ 2) was significantly greater in the IVUS-uncrossable group than in the IVUS-crossable group (26.1% vs. 10.7%, p = 0.001). The incidence of severe slow flow (TIMI grade ≤ 1) was also greater in the IVUS-uncrossable group than in the IVUS-crossable group (9.7% vs. 2.7%, p = 0.022). The multivariate logistic regression model showed a significant association between slow flow and pre-IVUS uncrossed lesions (vs. crossed lesions: odds ratio 2.103, 95% confidence interval 1.047–4.225, p = 0.037). In conclusion, the incidence of slow flow/severe slow flow just after RA was significantly greater in the IVUS-uncrossable lesions than in the IVUS-crossable lesions. Our study suggests the possibility that the IVUS-crossability can be used as a risk stratification of severe calcified lesions.

Further Validation of a Novel Acute Myocardial Infarction Risk Stratification (nARS) System for Patients with Acute Myocardial Infarction

Recently, we developed a novel acute myocardial infarction (AMI) risk stratification system (nARS), which stratifies AMI patients into low- (L), intermediate- (I), and high- (H) risk groups. We have shown that the nARS shortened the length of intensive care unit (ICU) stay as well as that of hospitalization. However, the incidence of AMI-related adverse outcomes has not been fully investigated. The purpose of this study was to investigate the incidence of severe complications requiring ICU care among the 3 risk groups stratified by nARS. We retrospectively reviewed AMI patients between October 2016 and December 2018. A total of 592 patients were divided into the L- (n = 285), I- (n = 124), and H- (n = 183) risk groups. The primary endpoint was in-hospital complications requiring ICU care defined as death/cardiopulmonary arrest, shock, stroke, atrioventricular block, and respiratory failure. Among 592 patients, 239 (40.4%) developed at least 1 complication requiring ICU care, but only 28 (11.7%) developed complications in general wards. Complications requiring ICU care were most frequently observed in the H-risk group (68.9%), followed by the I-risk group (50.8%), and least in the L-risk group (17.5%) (P < 0.001). Complications requiring ICU care that occurred in the general wards were more frequently observed in the H-risk group (8.7%) compared to the I-risk (3.2%) and L-risk (2.8%) groups (P = 0.009). In conclusion, complications requiring ICU care rarely happened in the general wards, and were less in the I- and L-risk groups than in the H-risk group. These results validated the nARS, and might support the widespread use of nARS.

The diagonal branches and outcomes in patients with anterior ST- elevation myocardial infarction

BACKGROUND

The management of diagonal branch (D) occlusion is still controversary. The association between the flow loss of D and the prognosis remains unclear. We aim to detect the impact of D flow on cardiac function and clinical outcomes in patients with anterior ST-segment elevation myocardial infarction (STEMI).

METHODS

Patients with anterior STEMI undergoing primary percutaneous coronary intervention (PCI) at our clinic between October 2015 and October 2018were reviewed. Anterior STEMI due to left anterior descending artery (LAD) occlusion with or without loss of the main D flow (TIMI grade 0-1 or 2-3) was enrolled in the analysis. The short- and long-term incidence of major adverse cardiac events (MACEs, a composite of all-cause death, target vessel revascularization and reinfarction) and left ventricular ejection fraction (LVEF) were analyzed.

RESULTS

A total of 392 patients (mean age of 63.9 years) with anterior STEMI treated with primary PCI was enrolled in the study. They were divided into two groups, loss (TIMI grade 0-1, n = 69) and no loss (TIMI grade2-3, n = 323) of D flow, before primary PCI. Compared with the group without loss of D flow, the group with loss of D flow showed a lower LVEF post PCI (41.0% vs. 48.8%, p = 0.003). Meanwhile, loss of D flow resulted in the higher in-hospital, one-month, and 18-month incidence of MACEs, especially in all-cause mortality (all p < 0.05). Landmark analysis further indicated that the significant differences in 18-month outcomes between the two groups mainly resulted from the differences during the hospitalization. In addition, multivariate Cox proportional hazards analysis found that D flow loss before primary PCI was independent factor predicting short- and long-term outcomes in patients with anterior STEMI.

CONCLUSION

Loss of the main D flow in anterior STEMI patients was independently associated with the higher in-hospital incidences of MACEs and all-cause death as well as the lower LVEF.

Determinants of Improvement of Mid-term Ejection Fraction in Patients with Acute Myocardial Infarction

Persistent severe left ventricular (LV) systolic dysfunction after acute myocardial infarction (AMI) is associated with increased morbidity and mortality, whereas mid-term recovery of LV systolic function after AMI is associated with better long-term outcomes. The purpose of this study was to investigate the determinants of mid-term improvement of LV ejection fraction (EF) in AMI patients. We included 210 AMI patients who had modified Simpson EF both at the index admission and mid-term follow up. The difference of EF between the index admission and mid-term follow-up was calculated in all study patients. The EF improvement group was defined as mid-term ≥ 10% EF increase compared with the index admission EF. Of 210 AMI patients, 46 (21.9%) were allocated to the EF improvement group and 164 (78.1%) to the non-EF improvement group. Brain natriuretic peptide (BNP) at the timing of admission was significantly greater in the EF improvement group (735.8 ± 1077.6 pg/mL) than in the non-EF improvement group (239.0 ± 419.8 pg/mL) (P < 0.001). Multivariate logistic regression analysis revealed that log₁₀ BNP at the timing of admission (OR 3.36, 95% CI 1.69-6.66, P < 0.001) and left main trunk-left anterior descending artery (LM-LAD) as the infarct-related artery (OR 3.34, 95% CI 1.59-7.02, P = 0.001) were significantly associated with EF improvement. In conclusion, elevated BNP at the timing of admission and LM-LAD as the infarct-related artery were significantly associated with mid-term LVEF recovery. Our results support aggressive acute treatment for those severe AMI, because the possibility of mid-term LVEF recovery is greater compared with other AMI.

Association of Excessive Speed Reduction with Clinical Factors During Rotational Atherectomy

BACKGROUND

Although the manufacturer recommends that excessive speed reduction (>5000 rpm) be avoided during rotational atherectomy (RA) for safety, excessive speed reduction is sometimes observed in clinical practice. The purpose of the present study was to examine the factors associated with excessive speed reduction during RA.

METHODS

Lesions (n = 300) treated by RA were divided into 3 groups: a mild speed reduction group (≤5000 rpm) (n = 182), a moderate speed reduction group (>5000-≤10,000 rpm) (n = 97), and a severe speed reduction group (>10,000 rpm) (n = 21). Two multivariate logistic regression analyses was performed to investigate the factors associated with >5000 rpm speed reduction, and factors associated with >10,000 rpm speed reduction.

RESULTS

Multivariate logistic regression analysis revealed that an ostial right coronary artery (RCA) lesion (OR 6.13, 95% CI 1.82-20.70, P = 0.004) and total ablation time (every 10 s increase: OR 1.09, 95% CI 1.05-1.14, P < 0.001) were significantly associated with >5000 rpm speed reduction. An ostial RCA lesion (OR 14.17, 95% CI 3.85-52.23, P < 0.001), use of intra-aortic balloon pump support (OR 4.19, 95% CI 1.18-14.87, P = 0.03), and systolic blood pressure just before RA (every 10 mmHg increase: OR 1.25, 95% CI 1.02-1.52, P = 0.03) were significantly associated with >10,000 rpm speed reduction.

CONCLUSIONS

RA of ostial RCA lesions was significantly associated with excessive speed reduction during RA, which implies that RA of ostial RCA lesions is technically more difficult than RA of non-ostial RCA lesions.

Comparison of mid-term clinical outcomes after acute myocardial infarction in diabetic men between living alone and living together

Because living alone is associated with an increased risk of type 2 diabetes mellitus in men but not women, living alone may be a risk factor of cardiovascular events after acute myocardial infarction (AMI) in diabetic men. The aim of the present study was to investigate the association between living alone and mid-term clinical outcomes after AMI in diabetic men. We conducted a single center, retrospecitve study. The primary endpoint was the major adverse cardiovascular events (MACE) defined as the composite of all cause death, AMI, and target vessel revascularization. A total of 253 AMI men with diabetes mellitus were included from our hospital records, and divided into the living together group (n = 203) and the living alone group (n = 50). Median follow-up duration was 239 days (Q1: 94 days, Q3: 451 days). A total of 66 MACE was observed during the study period, and Kaplan-Meier curves were constructed to compare the MACE. The MACE was more frequently observed in the living alone group than the living together group (P = 0.041). Multivariate Cox regression analysis revealed that the living alone group was significantly associated with the MACE (Odds ratio: 1.770, 95% confidence interval 1.018-3.077, P = 0.043) after known clinical risk factors. In conclusion, living alone was significantly associated with the mid-term MACE after AMI in diabetic men. It may be important to provide multiple interventions including lifestyle guidance as well as sufficient acute medical care for such high-risk patients.