Transient no reflow following primary percutaneous coronary intervention

Coronary No-Reflow after Primary Percutaneous Coronary Intervention-Current Knowledge on Pathophysiology, Diagnosis, Clinical Impact and Therapy

Coronary no-reflow (CNR) is a frequent phenomenon that develops in patients with ST-segment elevation myocardial infarction (STEMI) following reperfusion therapy. CNR is highly dynamic, develops gradually (over hours) and persists for days to weeks after reperfusion. Microvascular obstruction (MVO) developing as a consequence of myocardial ischemia, distal embolization and reperfusion-related injury is the main pathophysiological mechanism of CNR. The frequency of CNR or MVO after primary PCI differs widely depending on the sensitivity of the tools used for diagnosis and timing of examination. Coronary angiography is readily available and most convenient to diagnose CNR but it is highly conservative and underestimates the true frequency of CNR. Cardiac magnetic resonance (CMR) imaging is the most sensitive method to diagnose MVO and CNR that provides information on the presence, localization and extent of MVO. CMR imaging detects intramyocardial hemorrhage and accurately estimates the infarct size. MVO and CNR markedly negate the benefits of reperfusion therapy and contribute to poor clinical outcomes including adverse remodeling of left ventricle, worsening or new congestive heart failure and reduced survival. Despite extensive research and the use of therapies that target almost all known pathophysiological mechanisms of CNR, no therapy has been found that prevents or reverses CNR and provides consistent clinical benefit in patients with STEMI undergoing reperfusion. Currently, the prevention or alleviation of MVO and CNR remain unmet goals in the therapy of STEMI that continue to be under intense research.

The Impact of Kidney Function on the Slow-Flow/No-Reflow Phenomenon in Patients Treated with Primary Percutaneous Coronary Intervention: Registry Analysis

OBJECTIVE

The objective of this study is to analyze the impact of declining kidney function on the occurrence of the slow-flow/no-reflow phenomenon in patients with ST-elevation myocardial infarction (STEMI) treated with primary PCI (pPCI), as well as the analysis of the prognostic impact of the slow-flow/no-reflow phenomenon on short- and long-term mortality in these patients.

METHODS

We analyzed 3,115 consecutive patients. A value of the glomerular filtration rate (eGFR) at the time of admission of eGFR <90 ml/min/m2 was considered a low baseline eGFR. The follow-up period was 8 years.

RESULTS

The slow-flow/no-reflow phenomenon through the IRA was registered in 146 (4.7%) patients. Estimated GFR of <90 ml/min/m2 was an independent predictor for the occurrence of the slow-flow/no-reflow phenomenon (OR 2.91, 95% CI 1.25-3.95, p < 0.001), and the risk for the occurrence of the slow-flow/no-reflow phenomenon increased with the decline of the kidney function: eGFR 60-89 ml/min/m2: OR 1.94 (95% CI 1.22-3.07, p = 0.005), eGFR 45-59 ml/min/m2: OR 2.55 (95% CI 1.55-4.94, p < 0.001), eGFR 30-44 ml/min/m2: OR 2.77 (95% CI 1.43-5.25, p < 0.001), eGFR 15-29 ml/min/m2: OR 5.84 (95% CI 2.84-8.01, p < 0.001). The slow-flow/no-reflow phenomenon was a strong independent predictor of short- and long-term all-cause mortality: 30-day mortality (HR 2.62, 95% CI 1.78-3.57, p < 0.001) and 8-year mortality (HR 2.09, 95% CI 1.49-2.09, p < 0.001).

CONCLUSION

Reduced baseline kidney function was an independent predictor for the occurrence of the slow-flow/no-reflow phenomenon, and its prognostic impact started with the mildest decrease in eGFR (below 90 ml/min/m2) and increased with its further decline. The slow-flow/no-reflow phenomenon was a strong independent predictor of mortality in the short- and long-term follow-up of the analyzed patients.

Serum cystatin C levels relate to no-reflow phenomenon in percutaneous coronary interventions in ST-segment elevation myocardial infarction

Background/Aim

No-reflow is a serious and frequent event during primary percutaneous coronary intervention (PPCI) for acute ST segment elevation myocardial infarction (STEMI). The aim of this study was to identify possible predictors for no-reflow.

Patients and methods

We investigated 218 patients with acute anterior STEMI who underwent PPCI from December 2016 to December 2018. No-reflow was defined as a coronary TIMI flow grade of ≤ 2. TIMI flow grade 3 was defined as normal reflow.

Results

In our study, the no-reflow phenomenon was observed in 39 patients (18%) during angiography. The patients of no-reflow group were found to be more older, diabetics, longer pain-to-balloon time, lower blood pressure, higher platelet counts and higher levels of D-Dimer and Cystatin C (Cys-C). In multivariate logistic regression analysis, only diabetes (OR = 0.371, 95% CI: 0.157–0.872, P = 0.023), longer pain-to-balloon time (OR = 1.147, 95% CI: 1.015–1.297, P = 0.028) and higher Cys-C level (OR = 10.07, 95% CI: 2.340–43.377, P = 0.002) were predictors for no-reflow.

Conclusion

Cys-C might be a useful predictor for the no-reflow phenomenon after PPCI in STEMI patients. It might help to screen STEMI patients with high risk of no-reflow on admission.

Long-term clinical outcomes of transient and persistent no-reflow following percutaneous coronary intervention (PCI): a multicentre Australian registry

AIMS

The aim of the study was to evaluate long-term outcomes of transient versus persistent no-reflow.

METHODS AND RESULTS

A total of 17,547 patients with normal flow post percutaneous coronary intervention (PCI) were compared to 590 patients (3.2%) with transient no-reflow and 144 patients (0.8%) with persistent no-reflow. Long-term all-cause mortality was obtained by linkage with the National Death Index (NDI). No-reflow patients were more likely to have presented with ST-elevation myocardial infarction (STEMI), out-of-hospital cardiac arrest (OHCA) or cardiogenic shock (all p<0.01). Long-term NDI-linked all-cause mortality was highest in patients with persistent no-reflow (31%) followed by transient no-reflow (22%) and normal flow (14%) over a median follow-up of 5.2, 5.5 and 4.5 years, respectively (all p<0.0001). Kaplan-Meier survival estimates demonstrated a graded increase in all-cause mortality from normal flow, to transient to persistent no-reflow (p<0.01), with the highest mortality occurring early (<30 days) in the persistent no-reflow group (p<0.0001). Multivariate Cox proportional hazards modelling identified glomerular filtration rate <30 mL/min, ejection fraction <30%, persistent no-reflow and transient no-reflow as independent predictors of increased hazard for all-cause mortality (all p<0.05).

CONCLUSIONS

Transient and persistent no-reflow were associated with a stepwise reduction in long-term survival. The presence of even transient no-reflow appears to be an important predictor of adverse long-term outcome.

Association of slow flow with clinical factors in intravascular ultrasound-guided percutaneous coronary intervention for patients with left main trunk-acute myocardial infarction

BACKGROUND

Slow flow can be fatal in primary percutaneous coronary interventions for left main trunk (LMT)-acute myocardial infarction (AMI), however, risk factors for slow flow in LMT-AMI have not been well investigated. Intravascular ultrasound (IVUS) may help to stratify the high-risk lesion for slow flow in LMT-AMI.

METHODS

A total of 51 LMT-AMI were included as the study population, and were divided into the slow-flow group (n=22) and the non-slow-flow group (n=29). Slow flow was defined as either transient or persistent Thrombolysis in Myocardial Infarction (TIMI) flow grade ≤2.

RESULTS

The incidence of in-hospital death was higher in the slow-flow group (27.3%) than the non-slow-flow group (10.3%) without reaching statistical significance (p=0.116). Although the reference diameter measured by angiography was not different between the two groups, the vessel diameter measured by IVUS was significantly longer in the slow-flow group (5.22±0.69mm) than in the non-slow-flow group (4.50±0.47mm) (p<0.001). Multivariate logistic regression analyses revealed that the vessel diameter by IVUS (OR 27.487, 95%CI 3.975-190.062, p=0.001) and the vessel area by IVUS (OR 1.458, 95%CI 1.160-1.832, p=0.001) were significantly associated with slow flow.

CONCLUSIONS

In LMT-AMI, the vessel diameter measured by IVUS was closely associated with slow flow, while the reference diameter measured by angiography was not associated with slow flow. IVUS would be important to find high-risk features for slow flow in LMT-AMI.

High cystatin C levels predict long-term mortality in patients with ST-segment elevation myocardial infarction undergoing late percutaneous coronary intervention: A retrospective study

Objectives

Late percutaneous coronary intervention (PCI) in patients with ST‐segment elevation myocardial infarction (STEMI), defined as time of PCI > 7 days from symptom onset, is a common practice with clinical benefits. This study aimed to evaluate the predictive value of admission cystatin C (cys C) level on long‐term mortality in STEMI patients receiving late PCI.

Methods

Medical records of STEMI patients who were hospitalized between 2009 and 2011 from eight PCI‐capable hospitals in Northwest China were retrospectively analyzed. Cys C level ≥ 1.105 mg/L was considered as the best predictor of long‐term mortality based on the receiver‐operating characteristic analysis. Patients were followed up by phone or face‐to‐face interviews, and the long‐term mortality was obtained by reviewing medical records.

Results

The final analysis included 716 STEMI patients who received late PCI and had available cys C levels prior to PCI, and 524 were assigned into the high cys C group and 192 the low cys C group. Patients were followed up for an average length of 40.37 months. Compared with the low cys C group, the high cys C group had a higher long‐term all‐cause mortality (10.4% vs 2.9%, P < 0.001) and a higher cardiac mortality (6.8% vs 2.1%, P = 0.004). Multivariate Cox regression analysis showed that high cys C level was an independent predictor for both long‐term all‐cause mortality and cardiac mortality.

Conclusions

High cys C level at admission is an independent predictor of long‐term mortality in STEMI patients undergoing late PCI.

Identification of High-Risk Patients After ST-Segment–Elevation Myocardial Infarction

Background—

The incidence of angiographic no reflow (NR) and microvascular obstruction (MVO) at cardiac magnetic resonance is significantly different. The aim of this study was to investigate the occurrence of NR and MVO in a cohort of consecutive patients with ST-segment–elevation myocardial infarction treated with primary percutaneous coronary interventions.

Methods and Results—

In this prospective study, 88 consecutive ST-segment–elevation myocardial infarction patients were enrolled within 12 hours from symptoms onset. All patients underwent cardiac magnetic resonance between 2 and 5 days after primary percutaneous coronary interventions. NR was defined as thrombolysis in myocardial infarction flow grade ≤2 and as myocardial blush grade <2. Presence of early or late MVO was assessed 4 and 10 to 15 minutes after gadolinium injection. Thirty-one patients (36%) had evidence of NR, whereas 58 (67%) had MVO. One NR patient did not have MVO. In contrast, NR was present in 30 of 58 MVO patients. MVO patients had higher troponin T peak ( P <0.0001), larger late gadolinium enhancement area ( P <0.0001), and lower left ventricular ejection fraction ( P <0.001) because of an increased end-systolic volume ( P =0.015). In contrast, patients with NR had higher troponin T peak ( P =0.006) but similar late gadolinium enhancement area ( P =0.24) compared with those without NR. Major cardiovascular adverse events–free survival was worse in patients with MVO ( P =0.014), although it was similar in patients with and without NR ( P =0.33). The independent predictors of major cardiovascular adverse events were MVO (hazard ratio, 3.418; P =0.046) and ischemic time (hazard ratio, 1.016; P <0.001). MVO was a strong predictor of target lesion revascularization occurrence ( P =0.017 for log-rank test).

Conclusions—

Compared with coronary angiography performed soon after recanalization of the culprit artery, cardiac magnetic resonance performed during index hospitalization provides better prognostic stratification of ST-segment–elevation myocardial infarction patients treated with primary percutaneous coronary interventions. Another novel finding of our study is a significantly increased rate of clinically driven target lesion revascularization in the index event culprit vessel in patients with MVO.

Comparison of mid-term clinical outcomes between "complete full-metal jacket strategy" versus "incomplete full-metal jacket strategy" for diffuse right coronary artery stenosis with drug-eluting stents

BACKGROUND

The optimal strategy for diffuse right coronary artery (RCA) stenosis remains unclear.

OBJECTIVE

The objective of this study was to compare the mid-term outcomes of "complete full-metal jacket (c-FMJ) stenting strategy" with "incomplete full-metal jacket (i-FMJ) stenting strategy" for the diffuse long RCA lesion using drug-eluting stents (DES).

METHODS

Between July 2007 and October 2015, 121 patients underwent percutaneous coronary intervention (PCI) for diffuse RCA lesions using DES. Fifty-three patients underwent c-FMJ PCI, whereas 68 patients underwent i-FMJ. Thirty patients received angiographical follow-up in the c-FMJ group, while 34 patients received angiographical follow-up in the i-FMJ group. The primary endpoint was major adverse cardiac events (MACE): cardiac death, stent thrombosis (ST), target lesion revascularization (TLR), and target vessel revascularization (TVR).

RESULTS

The incidence of MACE was significantly lower in the c-FMJ group (13.3%) as compared to the i-FMJ group (41.2%) (p=0.013). There was no cardiac death in either group. The incidence of ST was comparable between the i-FMJ group (2.9%) and c-FMJ group (3.3%) (p=1.00), while TLR was significantly less in the c-FMJ group (6.7%) compared to the i-FMJ group (32.4%) (p=0.011).

CONCLUSIONS

The mid-term MACE was significantly less in the c-FMJ group than in the i-FMJ group, indicating that c-FMJ stenting was a favorable strategy for the diffuse long RCA lesion.

Long-Term Clinical Outcomes of Transient and Persistent No Reflow Phenomena following Percutaneous Coronary Intervention in Patients with Acute Myocardial Infarction

Background and Objectives

There is limited information on the transient or persistent no reflow phenomenon in patients with acute myocardial infarction (AMI) undergoing percutaneous coronary intervention (PCI).

Subjects and Methods

The study analyzed 4329 patients with AMI from a Korean multicenter registry who underwent PCI using coronary stents (2668 ST-elevation and 1661 non-ST-elevation myocardial infarction [MI] patients): 4071 patients without any no reflow, 213 with transient no reflow (no reflow with final thrombolysis in myocardial infarction [TIMI] flow grade 3), and 45 with persistent no reflow (no reflow with final TIMI flow grade≤2). The primary endpoint was all-cause mortality during 3-year follow-up. We also analyzed the incidence of cardiac mortality, non-fatal MI, re-hospitalization due to heart failure, target vessel revascularization, and stent thrombosis.

Results

The persistent no reflow group was associated with higher all-cause mortality (hazard ratio [HR] 1.98, 95% confidence interval [CI] 1.08-3.65, p=0.028) and cardiac mortality (HR 3.28, 95% CI 1.54-6.95, p=0.002) compared with the normal reflow group. Transient no reflow increased all-cause mortality only when compared with normal reflow group (HR 1.58, 95% CI 1.11-2.24, p=0.010). When comparing transient and persistent no reflow, persistent no reflow was associated with increased all-cause mortality (46.7 vs. 24.4%, log rank p=0.033).

Conclusion

The persistent no reflow phenomenon was associated with a poor in-hospital outcome and increased long-term mortality mainly driven by increased cardiac mortality compared to the transient no reflow phenomenon or normal reflow.

Association of serum cystatin C levels with myocardial perfusion and cardiac functional recovery in patients with anterior wall ST elevation myocardial infarction treated with primary coronary intervention

This study sought to investigate the association of baseline serum cystatin C levels with myocardial perfusion and cardiac functional recovery in patients with ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PPCI). 108 patients with a first anterior STEMI who underwent PPCI were enrolled. Serum cystatin C was measured by immunoturbidimetric method. Patients were divided into two groups according to the median cystatin C levels on admission: group 1 (≥median, n = 54) and group 2 (<median, n = 54). Myocardial perfusion was assessed by angiographic criteria, ST-segment resolution, and the index of microcirculatory resistance (IMR). Echocardiographic wall motion score index was analyzed on admission and at 6-month follow-up. Patients with angiographically, electrocardiographically no-reflow had significantly higher cystatin C levels on admission. Patients with an IMR ≥33.7 U also had significantly higher cystatin C levels. The WMSI showed a greater improvement in group 2 than in group 1 and there was a significant negative correlation between improvement of WMSI and the cystatin C levels. There was no significant difference in MACEs between the 2 groups. However, congestive heart failure (CHF) was observed significantly more frequent in group 1 than in group 2 (18.5 vs. 5.6 %, p = 0.022). Multivariate logistic regression analysis demonstrated that cystatin C levels at admission were a significant independent predictor of angiographic no-reflow and the development of CHF at 6-month follow-up. Elevated cystatin C levels at admission were independently associated with impaired myocardial perfusion, poor cardiac functional recovery and development of CHF in patients with anterior STEMI undergoing PPCI.

Impact of oral beta-blocker therapy on mortality after primary percutaneous coronary intervention for Killip class 1 myocardial infarction

The use of beta-blockers therapy has been recommended to reduce mortality in patients with left ventricular dysfunction after acute myocardial infarction (AMI). Primary percutaneous coronary intervention (PCI), which has become the mainstay of treatment for AMI, is associated with a lower mortality than fibrinolysis. The benefits of beta-blockers after primary PCI in AMI patients without pump failure are unclear. We hypothesized that oral beta-blocker therapy after primary PCI might reduce the mortality in AMI patients without pump failure. The assessment of lipophilic vs. hydrophilic statin therapy in acute myocardial infarction (ALPS-AMI) study was a multi-center study that enrolled 508 AMI patients to compare the efficacy of hydrophilic and lipophilic statins in secondary prevention after myocardial infarction. We prospectively tracked cardiovascular events for 3 years in 444 ALPS-AMI patients (median age 66 years; 18.2 % women) who had Killip class 1 on admission and were discharged alive. The primary endpoint was all-cause mortality. The 3-year follow-up was completed in 413 patients (93.0 %). During this follow-up, 21 patients (4.7 %) died. In Kaplan–Meier analysis, patients on beta-blockers had a significantly lower incidence of all-cause mortality (2.7 vs. 7.3 %, log-rank p = 0.025). After adjusting for the calculated propensity score for using beta-blockers, their use remained an independent predictor of all-cause mortality (hazard ratio 0.309; 95 % confidence interval 0.116–0.824; p = 0.019). In the statin era, the use of beta-blocker therapy after primary PCI is associated with lower mortality in AMI patients with Killip class 1 on admission.