Acute kidney injury is associated with microvascular myocardial damage following myocardial infarction

Development and validation of a prognostic model based on clinical laboratory biomarkers to predict admission to ICU in Omicron variant-infected hospitalized patients complicated with myocardial injury

Aims

The aim of this study was to develop and validate a prognostic model based on clinical laboratory biomarkers for the early identification of high-risk patients who require intensive care unit (ICU) admission among those hospitalized with the Omicron variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and complicated with myocardial injury (MI).

Methods

This single-center study enrolled 263 hospitalized patients with confirmed Omicron variant infection and concurrent MI. The patients were randomly divided into training and validation cohorts. Relevant variables were collected upon admission, and the least absolute shrinkage and selection operator (LASSO) was used to select candidate variables for constructing a Cox regression prognostic model. The model's performance was evaluated in both training and validating cohorts based on discrimination, calibration, and net benefit.

Results

Of the 263 eligible patients, 210 were non-ICU patients and 53 were ICU patients. The prognostic model was built using four selected predictors: white blood cell (WBC) count, procalcitonin (PCT) level, C-reactive protein (CRP) level, and blood urea nitrogen (BUN) level. The model showed good discriminative ability in both the training cohort (concordance index: 0.802, 95% CI: 0.716-0.888) and the validation cohort (concordance index: 0.799, 95% CI: 0.681-0.917). For calibration, the predicted probabilities and observed proportions were highly consistent, indicating the model's reliability in predicting outcomes. In the 21-day decision curve analysis, the model had a positive net benefit for threshold probability ranges of 0.2 to 0.8 in the training cohort and nearly 0.2 to 1 in the validation cohort.

Conclusion

In this study, we developed a clinically practical model with high discrimination, calibration, and net benefit. It may help to early identify severe and critical cases among Omicron variant-infected hospitalized patients with MI.

Impact of care bundles on the occurrence and outcomes of acute kidney injury among patients with ST-segment elevation myocardial infarction

BACKGROUND

Several reports suggested that compliance with acute kidney injury care bundles among hospitalized patients resulted in improved kidney and patient outcomes. We investigated the effect of acute kidney injury care bundle utilization on the incidence of acute kidney injury and renal outcomes in a large cohort of myocardial infarction patients treated with percutaneous coronary intervention.

METHODS

We included patients with myocardial infarction admitted following percutaneous coronary intervention between January 2008 and December 2020. From January 2016, acute kidney injury care bundle was implemented in our cardiac intensive care unit. Acute kidney injury care bundle consisted of simple standardized investigations and interventions, including strict monitoring of serum creatinine and urine analysis, planning investigations, treatment, and guidance about seeking nephrologist advice. Patients' records were evaluated for the occurrence of acute kidney injury, its severity, and recovery, before and after the implementation of acute kidney injury care bundle.

RESULTS

We included 2646 patients (1941 patients in the years 2008-2015 and 705 patients in the years 2016-2020). Implementation of care bundles resulted in a significant decrease in the occurrence of acute kidney injury from 190/1945 to 42/705 (10-6%; p < 0.001), with a trend for lower acute kidney injury score > 1 (20% vs. 25%; p = 0.07) and higher acute kidney injury recovery (62% vs. 45%, p = 0.001). Using a multivariable regression model, the use of care bundles resulted in a 45% decrease in the relative risk for acute kidney injury (HR 0.55, 95% CI 0.37-0.82, p < 0.001).

CONCLUSION

Among patients with ST-elevation myocardial infarction, treated with percutaneous coronary intervention and admitted to our cardiac intensive care unit over the period January 2008-December 2020, compliance with acute kidney injury care bundle was independently associated with a significant decrease in occurrence of acute kidney injury and with better renal outcomes following acute kidney injury. Further interventions, such as e-alert systems for acute kidney injury, could improve utilization of the acute kidney injury care bundle and optimize its clinical benefits.

Risk factors associated with contrast-associated acute kidney injury in ST-segment elevation myocardial infarction patients: a systematic review and meta-analysis

OBJECTIVE

The objective of this systematic review and meta-analysis was to evaluate the risk factors for contrast-associated acute kidney injury (CA-AKI) in ST-elevation myocardial infarction patients treated with primary percutaneous coronary intervention.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

We searched the databases of PubMed, Embase and Ovid, up to February 2022, for observational studies that investigated the association between risk factors and CA-AKI.

RESULTS

A total of 21 studies were included in the meta-analysis. Of the total 22 015 participants, 2728 developed CA-AKI. Pooled incidence was 11.91% (95% CI 9.69%, 14.14%). Patients with CA-AKI were more likely to be older, female, also had comorbidities (hypertension, diabetes, previous heart failure). Smoking (OR: 0.60; 95% CI 0.52, 0.69) and family history of CAD (coronary artery disease) (OR: 0.76; 95% CI 0.60, 0.95) were associated with lower risk of CA-AKI. Left anterior descending (LAD) artery occlusion (OR: 1.39; 95% CI 1.21, 1.59), left main disease (OR: 4.62; 95% CI 2.24, 9.53) and multivessel coronary disease (OR: 1.33; 95% CI 1.11, 1.60) were risk factors for CA-AKI. Contrast volume (weighted mean difference: 20.40; 95% CI 11.02, 29.79) was associated with increased risk in patients receiving iso-osmolar or low-osmolar non-ionic contrast.

CONCLUSIONS

In addition to the known risk factors, LAD artery infarction, left main disease and multivessel disease are risk factors for CA-AKI. The unexpected favourable association between smoking, as well as family history of CAD, and CA-AKI requires further investigation.

PROSPERO REGISTRATION NUMBER

CRD42021289868.

The impact of hyperglycaemic crisis episodes on long-term outcomes for inpatients presenting with acute organ injury: A prospective, multicentre follow-up study

BACKGROUND

The long-term clinical outcome of poor prognosis in patients with diabetic hyperglycaemic crisis episodes (HCE) remains unknown, which may be related to acute organ injury (AOI) and its continuous damage after hospital discharge. This study aimed to observe the clinical differences and relevant risk factors in HCE with or without AOI.

METHODS

A total of 339 inpatients were divided into an AOI group (n=69) and a non-AOI group (n=270), and their differences and risk factors were explored. The differences in clinical outcomes and prediction models for evaluating the long-term adverse events after hospital discharge were established.

RESULTS

The mortality among cases complicated by AOI was significantly higher than that among patients without AOI [8 (11.59%) vs. 11 (4.07%), Q = 0.034] during hospitalization. After a 2-year follow-up, the mortality was also significantly higher in patients with concomitant AOI than in patients without AOI after hospital discharge during follow-up [13 (21.31%) vs. 15 (5.8%), Q < 0.001]. The long-term adverse events in patients with concomitant AOI were significantly higher than those in patients without AOI during follow-up [15 (24.59%) vs. 31 (11.97%), Q = 0.015]. Furthermore, Blood β-hydroxybutyric acid (P = 0.003), Cystatin C (P <0.001), serum potassium levels (P = 0.001) were significantly associated with long-term adverse events after hospital discharge.

CONCLUSIONS

The long-term prognosis of HCE patients complicated with AOI was significantly worse than that of HCE patients without AOI. The laboratory indicators were closely correlated with AOI, and future studies should explore the improvement of clinical outcome in response to timely interventions.

Risk Factors and Outcome of Acute Kidney Injury following Acute Myocardial Infarction-A Case Series Study from 2009 to 2019

Background: Historically, acute kidney injury (AKI) has been a common severe complication of acute myocardial infarction (MI). As percutaneous coronary interventions have become more widely used, AMI outcomes have significantly improved. However, post-AMI AKI epidemiology and its associated factors are not well-understood in the age of interventional cardiology. Materials and methods: This is a retrospective study examining changes in creatinine levels in all patients admitted for AMI in a single medical center between August 2009 and February 2019. KDIGO criteria were used to define the different stages of post-AMI AKI. Results: The study included 1299 eligible cases, among which 213 (16.4%) developed AKI during AMI index admission; and 128 (60.1%), 46 (21.6%), and 39 (18.3%) were classified as KDIGO stages 1, 2, and 3, respectively. Compared with non-AKI subjects, the AKI group had a higher prevalence of non-STEMI (48.4% vs. 29.1%, p < 0.001), higher Killip class (3 or 4), and higher in-hospital mortality (15% vs. 2.5%, p < 0.001). During the index MI hospitalization, 13.6% (29/213) of the post-MI AKI patients received hemodialysis. Baseline abnormal creatinine (≥1.5 mg/dL), dyslipidemia, and more advanced KDIGO stages (2 or 3) were associated with an increased risk of requiring in-hospital hemodialysis. Moreover, a more advanced KDIGO stage (≥2) was correlated with higher all-cause in-hospital mortality. Conclusion: AMI patients remain at risk of AKI, which negatively affects their survival in the modern age.

Ultrasonic Image Features under the Intelligent Algorithm in the Diagnosis of Severe Sepsis Complicated with Renal Injury

This research was aimed at analyzing the diagnosis of severe sepsis complicated with acute kidney injury (AKI) by ultrasonic image information based on the artificial intelligence pulse-coupled neural network (PCNN) algorithm and at improving the diagnostic accuracy and efficiency of clinical severe sepsis complicated with AKI. In this research, 50 patients with sepsis complicated with AKI were collected as the observation group and 50 patients with sepsis as the control group. All patients underwent ultrasound examination. The clinical data of the two groups were collected, and the scores of acute physiology and chronic health assessment (APACHE II) and sequential organ failure assessment (SOFA) were compared. The ultrasonic image information enhancement algorithm based on artificial intelligence PCNN is constructed and simulated and is compared with the maximum between-class variance (OSTU) algorithm and the maximum entropy algorithm. The results showed that the PCNN algorithm was superior to the OSTU algorithm and maximum entropy algorithm in the segmentation results of severe sepsis combined with AKI in terms of regional consistency (UM), regional contrast (CM), and shape measure (SM). The acute physiology and chronic health evaluation (APACHE II) and sequential organ failure assessment (SOFA) scores in the observation group were substantially higher than those in the control group (P < 0.05). The interlobular artery resistance index (RI) in the observation group was substantially higher than that in the control group (P < 0.05). Moreover, the mean transit time (mTT) in the observation group was significantly higher than that in the control group (4.85 ± 1.27 vs. 3.42 ± 1.04), and the perfusion index (PI) was significantly lower than that in the control group (134.46 ± 17.29 vs. 168.37 ± 19.28), with statistical significance (P < 0.05). In summary, it can substantially increase ultrasonic image information based on the artificial intelligence PCNN algorithm. The RI, mTT, and PI of the renal interlobular artery level in ultrasound images can be used as indexes for the diagnosis of severe sepsis complicated with AKI.

Early Detection of Inflammation-Prone STEMI Patients Using the CRP Troponin Test (CTT)

Elevated concentrations of C-reactive protein (CRP) early during an acute coronary syndrome (ACS) may reflect the magnitude of the inflammatory response to myocardial damage and are associated with worse outcome. However, the routine measurement of both CRP and cardiac troponin simultaneously in the setting of ST-segment myocardial infarction (STEMI) is not used broadly. Here, we sought to identify and characterize individuals who are prone to an elevated inflammatory response following STEMI by using a combined CRP and troponin test (CTT) and determine their short- and long-term outcome. We retrospectively examined 1186 patients with the diagnosis of acute STEMI, who had at least two successive measurements of combined CRP and cardiac troponin (up to 6 h apart), all within the first 48 h of admission. We used Chi-Square Automatic Interaction Detector (CHAID) tree analysis to determine which parameters, timing (baseline vs. serial measurements), and cut-offs should be used to predict mortality. Patients with high CRP concentrations (above 90th percentile, >33 mg/L) had higher 30 day and all-cause mortality rates compared to the rest of the cohort, regardless of their troponin test status (above or below 118,000 ng/L); 14.4% vs. 2.7%, p < 0.01. Furthermore, patients with both high CRP and high troponin levels on their second measurement had the highest 30-day mortality rates compared to the rest of the cohort; 21.4% vs. 3.7%, p < 0.01. These patients also had the highest all-cause mortality rates after a median follow-up of 4.5 years compared to the rest of the cohort; 42.9% vs. 12.7%, p < 0.01. In conclusion, serial measurements of both CRP and cardiac troponin might detect patients at increased risk for short-and long-term mortality following STEMI. We suggest the future use of the combined CTT as a potential early marker for inflammatory-prone patients with worse outcomes following ACS. This sub-type of patients might benefit from early anti-inflammatory therapy such as colchicine and anti-interleukin-1ß agents.

Acute Kidney Injury Recovery Patterns in ST-Segment Elevation Myocardial Infarction Patients

Background: Acute kidney injury (AKI) is a frequent complication in patients with ST-segment elevation myocardial infarction (STEMI) undergoing percutaneous coronary intervention (PCI). Identification of different AKI recovery patterns may improve patient prognostic stratification. We investigated the clinical relevance of AKI recovery patterns among STEMI patients undergoing PCI. Methods: A retrospective study of 2943 STEMI patients undergoing PCI. The incidence of renal impairment, in-hospital complications, short and long-term mortality, were compared between patients without AKI, with early recovery defined as a return to baseline creatinine within 72 h, and no AKI recovery/delayed recovery defined as all other AKI cases. Results: A total of 255 (8.7%) patients developed AKI, of whom 124/255 (49%) patients had an early recovery, whereas 131/255 (51%) had no AKI recovery/delayed recovery. Patients without recovery were more likely to have in-hospital complications and higher long-term mortality (36.64% vs. 7.25%%; p < 0.001). In a multivariable regression model, the mortality hazard ratio (HR) for long term mortality remained significant for patients with no/delayed recovery AKI (HR 7.76, 95% CI 4.69 to 12.86, p < 0.001), and a strong trend among patients with resolving AKI (HR 2.09, 95% CI 0.933−4.687, p = 0.071). Conclusions: Among STEMI patients undergoing PCI, the recovery pattern of AKI is a valuable prognostic marker.

Association of plasma interleukin-6 with infarct size, reperfusion injury, and adverse remodelling after ST-elevation myocardial infarction

AIMS

Little is known about the clinical relevance of interleukin (IL)-6 in patients with acute ST-elevation myocardial infarction (STEMI). This study examined the possible associations of plasma IL-6 concentrations with infarct size (IS), reperfusion injury and adverse left ventricular remodelling (LVR), in STEMI patients treated with primary percutaneous coronary intervention (PCI).

METHODS AND RESULTS

We prospectively included 170 consecutive STEMI patients (median age 57 years, 14% women) treated with primary PCI between 2017 and 2019. Blood samples for biomarker analyses including IL-6 were collected on Day 2. Left ventricular ejection fraction (LVEF), IS, and reperfusion injury [microvascular obstruction (MVO) and intramyocardial haemorrhage (IMH)] were determined using cardiac magnetic resonance (CMR) imaging on Day 4. Left ventricular remodelling was defined as ≥10% increase in left ventricular end-diastolic volume from baseline to 4 months CMR follow-up. Patients with IL-6 concentrations ≥median (17 ng/L) showed a significantly lower LVEF (43% vs. 52%, P < 0.001), larger IS (22% vs. 13%, P < 0.001), larger MVO (1.9% vs. 0.0%, P < 0.001), and more frequent IMH (52% vs. 18%, P < 0.001). Left ventricular remodelling was more common in patients with IL-6 ≥ median (24% vs. 9%, P = 0.005). In both linear and binary multivariable regression analyses, IL-6 remained independently associated with lower LVEF [odds ratio (OR): 0.10, 95% confidence interval (CI) 0.02-0.42, P = 0.002], larger IS (OR: 5.29, 95% CI 1.52-18.40, P = 0.009), larger MVO (OR: 5.20, 95% CI 1.30-20.85, P = 0.020), with presence of IMH (OR: 3.73, 95% CI 1.27-10.99, P = 0.017), and adverse LVR (OR: 2.72, 95% 1.06-6.98, P = 0.038).

CONCLUSIONS

High concentrations of circulating plasma IL-6 on Day 2 after STEMI were independently associated with worse myocardial function, larger infarct extent, more severe reperfusion injury, and a higher likelihood for LVR, suggesting IL-6 as a useful biomarker of more serious outcome and potential therapeutic target.

CLINICAL TRIAL REGISTRATION

https://clinicaltrials.gov/ct2/show/NCT04113356;NCT04113356.

Cardiorenal Syndrome: Emerging Role of Medical Imaging for Clinical Diagnosis and Management

Cardiorenal syndrome (CRS) concerns the interconnection between heart and kidneys in which the dysfunction of one organ leads to abnormalities of the other. The main clinical challenges associated with cardiorenal syndrome are the lack of tools for early diagnosis, prognosis, and evaluation of therapeutic effects. Ultrasound, computed tomography, nuclear medicine, and magnetic resonance imaging are increasingly used for clinical management of cardiovascular and renal diseases. In the last decade, rapid development of imaging techniques provides a number of promising biomarkers for functional evaluation and tissue characterization. This review summarizes the applicability as well as the future technological potential of each imaging modality in the assessment of CRS. Furthermore, opportunities for a comprehensive imaging approach for the evaluation of CRS are defined.

C-Reactive Protein Apheresis as Anti-inflammatory Therapy in Acute Myocardial Infarction: Results of the CAMI-1 Study

Background: C-reactive protein (CRP) is a well-known marker of inflammation. It is less known that CRP mediates tissue damage in acute myocardial infarction (AMI) thus potentially worsening prognosis. A newly developed specific CRP adsorber allows efficient lowering of CRP levels and may improve survival.

Objectives: Aim of this multi-center, controlled, non-randomized first-in-man CRP apheresis in Acute Myocardial Infarction study (CAMI-1) was to investigate the relationship between CRP levels (CRP gradient), myocardial infarct size and function as well as safety and efficacy of CRP apheresis in the setting of acute ST-segment Elevation Myocardial Infarction (STEMI) in humans.

Methods: Eighty-three patients (45 apheresis, 38 controls) were recruited. CRP apheresis was performed 24 ± 12, 48 ± 12, and optionally 72 ± 12 h after onset of symptoms. First aphereses were performed at a median CRP concentration of 23.0 mg/L (range 9–279). In each apheresis session, 5,900 ± 400 mL plasma was processed via peripheral venous access. Primary study endpoint was a reduction in myocardial infarct size after STEMI as determined by cardiovascular magnetic resonance (CMR).

Results: In controls, the CRP concentration significantly correlated with infarct size (p = 0.002) and decreased myocardial function (p ≤ 0.001). The CRP concentration in apheresis patients did not correlate with infarct size (p = 0.66) or left ventricular (LV) function (p = 0.79) and global strains and therefore significantly differed from controls (p = 0.03 and p = 0.002). Three major adverse cardiac events occurred in the control group after 12 months, none occurred in the apheresis group. Mean CRP depletion achieved over all apheresis procedures was 53.0 ± 15.1%. Apheresis sessions were well-tolerated. Reduced infarct size in the apheresis group compared to the control group (primary endpoint) was not achieved according to the original statistical analysis plan. Taking into account the individual CRP levels, however, revealed significant results. Modifications of the analysis plan were introduced in order to recruit a sufficient number of patients.

Conclusions: This pilot study in humans reveals a correlation between CRP concentration and myocardial infarct size. CRP concentrations in STEMI can effectively be reduced by CRP apheresis without relevant side effects. CRP apheresis has the potential to interfere with deleterious aspects of STEMI. By lowering CRP levels, it resulted in the loss of correlation of CRP concentrations with myocardial infarct sizes as well as LV function. These results encourage a larger, randomized clinical trial.

Clinical Trial Registration:https://www.drks.de/drks_web/navigate.do?navigationId=trial.HTML&TRIAL_ID=DRKS00008988, DRKS00008988.

High sensitivity C-reactive protein is associated with worse infarct healing after revascularized ST-elevation myocardial infarction

BACKGROUND

The inflammatory response due to myocardial tissue injury in the setting of acute ST-elevation myocardial infarction (STEMI) is essential for proper local infarct healing. However, an excessive inflammatory response may aggravate myocardial damage and hampers infarct healing processes. The present study aimed to investigate the association of systemic inflammatory biomarkers with infarct size (IS) dynamics post-STEMI, using cardiac magnetic resonance (CMR) imaging.

METHODS

This prospective observational study included 245 STEMI patients treated with primary percutaneous coronary intervention (pPCI). Peak values of high-sensitivity C-reactive protein (hs-CRP), white blood cell count (WBCc) and fibrinogen were determined serially until 96 h after pPCI. Infarct healing, defined as relative IS reduction from baseline to 4 months after STEMI, was assessed using late gadolinium enhanced CMR imaging.

RESULTS

IS significantly decreased from 16% of left ventricular mass (LVM) (Interquartile range [IQR]:8-24) at baseline to 10% (IQR:5-17) at 4 months (p < 0.001). Relative IS reduction was 35% (IQR:8-50). Whereas peak WBCc (p = 0.926) and peak fibrinogen (p = 0.161) were not significantly associated with relative IS reduction, peak hs-CRP showed a significant association with IS reduction (p = 0.003). In multivariable logistic regression analysis, the association between peak hs-CRP and relative IS reduction remained significant after adjustment for baseline IS, hypertension, hs-cardiac troponin T and N-terminal pro B-type natriuretic peptide (odds ratio:0.35 [95% confidence interval:0.19-0.63]; p = 0.001).

CONCLUSIONS

In STEMI patients treated with pPCI, hs-CRP was independently associated with 4 months IS reduction as determined by CMR, suggesting a pathophysiological interplay between inflammation and adverse infarct healing in survivors of acute STEMI.

Effect of Combining Furosemide With Standard Hydration Therapy on Contrast-Induced Acute Kidney Injury Following Coronary Angiography or Intervention in a High-Risk Population

This study aimed to investigate whether combining furosemide with standard hydration therapy results in increased preventive effects on contrast-induced acute kidney injury (CI-AKI) following coronary angiography (CA) or percutaneous coronary intervention (PCI). Patients (n = 230) were enrolled in the study and were randomized to the furosemide group or the control group. Patients in the furosemide group received 0.2 to 0.5 mg/kg of furosemide as a continuous intravenous infusion for 24 hours postoperatively and the same standard hydration regimen received by the control group. Blood samples were obtained 24 hours before and 48 hours after the procedure and urine volume was recorded postprocedure. Patients were followed up for an average of 6 months after the procedure. The incidence of CI-AKI in the furosemide group was significantly lower than that in the control group (8.7% vs 18.3%, P = .034). Multivariate logistic regression showed that age-glomerular filtration rate-ejection fraction score and V/estimated glomerular filtration rate ratio were independent risk factors for CI-AKI. During the average 6-month follow-up, incidence of major adverse cardiovascular events (MACEs) in the furosemide group was also significantly lower. Furosemide combined with standard hydration therapy may reduce the incidence of CI-AKI and MACEs following CA or PCI.

Aortic Stiffness and Infarct Healing in Survivors of Acute ST-Segment-Elevation Myocardial Infarction

Background

In survivors of acute ST‐segment–elevation myocardial infarction (STEMI), increased aortic stiffness is associated with worse clinical outcome; however, the underlying pathomechanisms are incompletely understood. We aimed to investigate associations between aortic stiffness and infarct healing using comprehensive cardiac magnetic resonance imaging in patients with acute STEMI.

Methods and Results

This was a prospective observational study including 103 consecutive STEMI patients treated with primary percutaneous coronary intervention. Pulse wave velocity (PWV), the reference standard for aortic stiffness assessment, was determined by a validated phase‐contrast cardiac magnetic resonance imaging protocol within the first week after STEMI. Infarct healing, defined as relative infarct size reduction from baseline to 4 months post‐STEMI, was determined using late gadolinium‐enhanced cardiac magnetic resonance. Median infarct size significantly decreased from 17% of left ventricular mass (interquartile range 9% to 28%) at baseline to 12% (6% to 17%) at 4‐month follow‐up (P<0.001). Relative infarct size reduction was 36% (interquartile range 15% to 52%). Patients with a reduction >36% were younger (P=0.01) and had lower baseline NT‐proBNP (N‐terminal pro–B‐type natriuretic peptide) concentrations (P=0.047) and aortic PWV values (P=0.003). In a continuous (odds ratio 0.64 [95% CI, 0.49–0.84]; P=0.001) as well as categorical (PWV <7 m/s; odds ratio 4.80 [95% CI, 1.89–12.20]; P=0.001) multivariable logistic regression model, the relation between aortic PWV and relative infarct size reduction remained significant after adjustment for baseline infarct size, age, NT‐proBNP, and C‐reactive protein.

Conclusions

Aortic PWV independently predicted infarct size reduction as assessed by cardiac magnetic resonance, revealing a novel pathophysiological link between aortic stiffness and adverse infarct healing during the early phase after STEMI treated with contemporary primary percutaneous coronary intervention.

Relationship between admission Q waves and microvascular injury in patients with ST-elevation myocardial infarction treated with primary percutaneous coronary intervention

BACKGROUND

Using comprehensive cardiac magnetic resonance (CMR) imaging in patients suffering from ST-elevation myocardial infarction (STEMI) treated with primary percutaneous coronary intervention (pPCI), we sought to investigate the association of admission Q waves with microvascular injury (microvascular obstruction (MVO) and intramyocardial haemorrhage (IMH)).

METHODS

This prospective observational study included 195 STEMI patients treated with pPCI. Admission 12-lead electrocardiography was evaluated for the presence of pathological Q waves, defined as a Q wave duration of >30 ms and a depth of >0.1 mV. CMR was performed at 3 (interquartile range: 2-5) days after pPCI to determine infarct characteristics including MVO (late gadolinium enhancement) and IMH (T2* mapping).

RESULTS

Admission Q waves were observed in 53% of patients (n = 104). These patients had a significantly lower BMI (p = 0.005), more frequent left anterior descending artery as culprit lesion (p = 0.005), were less frequent smokers (p = 0.048) and had higher rates of pre-interventional TIMI flow 0 (p = 0.018). Patients with Q waves showed a significantly larger infarct size (19%vs.12% of left ventricular mass,p < 0.001), lower ejection fraction (49%vs.54%,p = 0.001), worse global strain parameters (all p < 0.005) and more severe microvascular injury (MVO: 68%vs.34%,p < 0.001; IMH: 40%vs.20%,p = 0.002). Q waves remained associated with both MVO (odds ratio: 5.23, 95% confidence interval: 2.58 to 10.58,p < 0.001) and IMH (odds ratio: 3.94, 95% confidence interval: 1.83 to 8.46,p < 0.001) after adjusting for potential confounders (culprit lesion, pre-interventional TIMI flow 0, total ischemia time, ST-segment elevation).

CONCLUSIONS

Admission Q waves, derived from the readily available ECG, emerged as independent early markers of CMR-determined microvascular injury in STEMI patients undergoing pPCI.