Frequency, determinants, and clinical relevance of acute coronary syndrome-like electrocardiographic findings in patients with acute aortic syndrome

Transesophageal Echocardiographic Evaluation of Coronary Blood Flow and the Initial Flap Assisting in the Surgical Decision-Making: A Case of Acute Type A Aortic Dissection

Acute aortic dissection is a life-threatening condition. Myocardial ischemia associated with dissection occurs due to direct extension into the coronary artery or indirect involvement of the coronary ostia secondary to the dissection flap. Thus, the surgical procedure may require coronary reconstruction, in addition to aortic replacement. We experienced a case in which coronary artery reconstruction could be avoided because intraoperative transesophageal echocardiography showed that the aortic flap did not obstruct the right coronary artery in systole, and pulsed Doppler imaging indicated that there was sufficient coronary blood flow. This case shows that it is critical to establish a correct and early diagnosis and to proceed with the appropriate treatment for patients with myocardial ischemia.

The impact of CK-MB elevation in patients with acute type A aortic dissection with coronary artery involvement

Background

Acute type A aortic dissection (ATAAD) is a fatal disease and requires emergency surgery. In particular, it is known that mortality is high when a coronary artery is involved. However, the degree of myocardial damage of the coronary acute artery involvement (ACI) varies and may or may not increase creatine kinase muscle and brain isoenzyme (CK-MB). It is unknown how CK-MB elevation affects the surgical outcome. This study compared the surgical results between the two groups of ACI with or without CK-MB elevation.

Methods

Among 348 patients who underwent an emergency operation for acute type A aortic dissection, there were 28 (8.0%) patients complicated by ACI and underwent additional coronary artery bypass grafting. We divided 26 of those patients into two groups; the MI group ( with CK-MB elevation) and the NMI group (without CK-MB elevation), and compared both groups.

Results

Of the 26, sixteen were in the MI group, and ten were in the NMI group. The average CK-MB in the MI group was 225.5 IU/L, and that in the NMI group was 13.5 IU/L. The mean time from onset to surgery was 248 min in the MI group and 250 min in the NMI group. There was statistical significance in mortality ( 69% vs. 13%, p = 0.03). There was no significance in major complications (ICU days, reintubation, reoperation, pneumonia, sepsis).

Conclusions

Acute coronary artery involvement was associated with 8.0% of patients with ATAAD, and 62% had myocardial ischemia with CK-MB elevation. The MI group had significantly higher mortality than the NMI group. It is crucial for cases with suspected ACI to obtain coronary perfusion as soon as possible to prevent CK-MB from elevating.

Extensive repair of acute type A aortic dissection through a partial upper sternotomy and using complete stent-graft replacement of the arch

BACKGROUND

Partial upper sternotomy (mini-ER) can be used in some adult cardiac surgeries but is seldom performed in the treatment of acute type A aortic dissection (AAAD). This study aimed to assess the feasibility and short-term outcomes of complete stent-graft replacement of the arch with triple-branched stent graft for AAAD through a mini-ER.

METHODS

From 2015 to 2018, 254 patients with AAAD underwent complete stent-graft replacement of the arch with a triple-branched stent graft. Replacement was performed with conventional full sternotomy (con-ER) in 142 patients and with mini-ER in the other 112 patients. Using propensity score matching, the clinical data were compared between 100 patients in the mini-ER group and 100 patients in the con-ER group.

RESULTS

After propensity score matching, there were no significant between-group differences in aortic cross-clamp time, cardiopulmonary bypass time, or total operative time. The amount of mediastinal drainage and number of red blood cell units were significantly lower in the mini-ER group compared with the con-ER group (P < .001). The intubation time was significantly shorter in the mini-ER group (P < .001). The treatment costs were also lower in the mini-ER group (P < .001). There were no significant between-group differences in 30-day mortality (9% vs 8%; P > .99) or postoperative complications.

CONCLUSIONS

This study shows that extensive repair of AAAD through a mini-ER is feasible. It was superior to con-ER in terms of blood loss, postoperative ventilation time, and treatment costs.

Characteristics and Outcomes of Patients Hospitalized With Suspected Acute Coronary Syndrome in Whom the Diagnosis is not Confirmed

Patients admitted with suspected acute coronary syndrome (ACS) in whom the diagnosis is not confirmed are poorly characterized. In a contemporary registry of consecutive patients hospitalized with suspected ACS as the primary diagnosis, we assessed characteristics on admission and in-hospital and 6-month mortality of patients discharged with other diagnoses and compared this subgroup with true ACS patients. Of 2557 patients included, 9.0% were discharged with a non-ACS diagnosis such as nonspecific chest pain, myopericarditis, stress cardiomyopathy, hemodynamic disturbances, heart failure, myocardial, pulmonary or valvular disease, or others. Compared with true ACS patients, those with other diagnoses were younger, more often female, and had less cardiovascular risk factors. Both groups had comparable rates of nonchest pain presentation and similar hemodynamic characteristics on admission. Non-ACS patients presented less often with Q waves or with ST-segment or T-wave changes and had a lower Global Registry of Acute Coronary Events score than true ACS patients. In-hospital (4.3 vs 4.0%, respectively, p = 0.834) and 6-month (5.4 vs 8.0%, respectively, p = 0.163) mortality rates were comparable in both groups. However, if patients in the non-ACS group were divided into subgroups with nonspecific chest pain (6.2% of total) or other diagnoses (2.8% of total), major differences in in-hospital (0.0 vs 13.9%, respectively, p < 0.001) and 6-month (0.7 vs 15.7%, respectively, p < 0.001) mortality rates would become apparent and remain after multivariable adjustment. In conclusion, in a non-negligible proportion of patients hospitalized with suspected ACS, this diagnosis is not confirmed. Prognosis of these patients follows a bimodal pattern, being excellent in those with nonspecific chest pain but worse than that of true ACS patients in the rest. Efforts are necessary to ensure prompt identification and early risk stratification of these patients allowing appropriate management decisions.

Troponin T elevation in acute aortic syndromes: Frequency and impact on diagnostic delay and misdiagnosis

AIMS

Despite troponin assay being a part of the diagnostic work up in many conditions with acute chest pain, little is known about its frequency and clinical implications in acute aortic syndromes (AASs). In our study we assessed frequency, impact on diagnostic delay, inappropriate treatments, and prognosis of troponin elevation in AAS.

METHODS AND RESULTS

Data were collected from a prospective metropolitan AAS registry (398 patients diagnosed between 2000 and 2013). Cardiac troponin test, using either standard or high sensitivity assay, was performed according to standard protocol used in chest pain units. Troponin T values were available in 248 patients (60%) of the registry population; the overall frequency of troponin positivity was 28% (ranging from 16% to 54%, using standard or high sensitivity assay respectively, p = 0.001). Troponin positivity was frequently associated with acute coronary syndromes (ACS)-like electrocardiogram findings, and with a twofold increased risk of long in-hospital diagnostic time (odds ratio (OR) 1.92, 95% confidence interval (CI) 1.05-3.52, p = 0.03). The combination of positive troponin and ACS-like electrocardiogram abnormalities resulted in a significantly increased risk of in-hospital delay/coronary angiography/antithrombotic therapy due to a misdiagnosis of ACS (OR 2.48, 95% CI 1.12-5.54, p = 0.02). However, troponin positivity was not associated with in-hospital mortality (OR 1.63, 95% CI 0.86-3.10, p = 0.131).

CONCLUSIONS

Troponin positivity was a frequent finding in AAS patients, particularly when a high sensitivity assay was employed. Abnormal troponin values were strongly associated with ACS-like electrocardiogram findings and with in-hospital diagnostic delay but apparently they did not influence in-hospital mortality.

Electrocardiography changes in acute aortic dissection-association with troponin leak, coronary anatomy, and prognosis

BACKGROUND

Electrocardiography (ECG) offers some information that may be used to prognosticate acute type A aortic dissection (AAOD) for short- and long-term mortality.

METHODS

We retrospectively analyzed the electrocardiograms of patients with AAOD admitted from March 2004 to March 2015. The frequency of ECG findings and their prognostic value on hospital and follow-up mortality were investigated. Findings pertaining to coronary involvement and troponin level were also examined.

RESULTS

A total of 120 men and 64 women were admitted. Acute ischemic changes were reported in 38.0%, whereas T inversion was the most common recorded abnormality, which occurred in 38.6%. Acute ST-elevation myocardial infarction was detected in 16.3%. Troponin increased in 36.6%; 21.9% of the patients underwent coronary angiography among which 70% were normal. Coronary involvement or troponin increase was not different in patients with acute ECG changes. During hospitalization, 45.7% of the patients died. In multivariate analyses, ST elevation in lead aVR was associated with higher hospital death (odds ratio, 5.30; 95% confidence interval, 1.09-25.73; P = .038), whereas QRS greater than 120 milliseconds was associated with long-term mortality (hazard ratio, 2.45; 95% confidence interval, 1.25-3.76; P = .006).

CONCLUSION

Acute ischemic ECG changes are common in AAOD, and a completely normal ECG is infrequently encountered. Acute ECG changes were not associated with the increased troponin or the presence of coronary lesions in angiography.

Frequency and implication of ST-T abnormalities on hospital admission electrocardiograms in patients with type A acute aortic dissection

Although patients with Stanford type A acute aortic dissection often show ST-T abnormalities at presentation, the frequency and implication of such findings remain unclear. To clarify these points, admission electrocardiograms from 233 patients admitted ≤6 hours after symptom onset who underwent emergency surgery for type A acute aortic dissection were studied. The prevalence of electrocardiographic (ECG) patterns was 51% for ST-T abnormalities (4% for ST-segment elevation and 47% for ST-segment depression and/or negative T waves), 30% for normal ECG findings or no significant ST-T changes, and 19% for ECG confounders such as bundle branch block or left ventricular hypertrophy. Patients with ST-T abnormalities had higher prevalence of pericardial effusion (48% vs 9% and 38%), cardiac tamponade (28% vs 3% and 18%), moderate or severe aortic regurgitation (28% vs 7% and 18%), shock on admission (34% vs 3% and 13%), coronary ostial involvement (14% vs 1% and 2%), concomitant coronary artery bypass surgery (9% vs 1% and 0%), and in-hospital mortality (11% vs 1% and 4%) compared with patients with normal ECG findings or no significant ST-T changes and those who had ECG confounders (p <0.05 for all). On multivariate analysis, ST-T abnormalities were the only independent predictor of in-hospital mortality (odds ratio 3.87, 95% confidence interval 1.02 to 14.7, p = 0.035). In conclusion, about 50% of patients who underwent emergency surgery for type A acute aortic dissection had ST-T abnormalities, characterized predominantly by ST-segment depression or negative T waves, in the acute phase. ST-T abnormalities were associated with more complicated features and independently predicted in-hospital death.

Evidence, lack of evidence, controversy, and debate in the provision and performance of the surgery of acute type A aortic dissection

Acute type A aortic dissection is a lethal condition requiring emergency surgery. It has diverse presentations, and the diagnosis can be missed or delayed. Once diagnosed, decisions with regard to initial management, transfer, appropriateness of surgery, timing of operation, and intervention for malperfusion complications are necessary. The goals of surgery are to save life by prevention of pericardial tamponade or intra-pericardial aortic rupture, to resect the primary entry tear, to correct or prevent any malperfusion and aortic valve regurgitation, and if possible to prevent late dissection-related complications in the proximal and downstream aorta. No randomized trials of treatment or techniques have ever been performed, and novel therapies-particularly with regard to extent of surgery-are being devised and implemented, but their role needs to be defined. Overall, except in highly specialized centers, surgical outcomes might be static, and there is abundant room for improvement. By highlighting difficulties and controversies in diagnosis, patient selection, and surgical therapy, our over-arching goal should be to enfranchise more patients for treatment and improve surgical outcomes.

Correlates of Delayed Recognition and Treatment of Acute Type A Aortic Dissection

Background—

In acute aortic dissection, delays exist between presentation and diagnosis and, once diagnosed, definitive treatment. This study aimed to define the variables associated with these delays.

Methods and Results—

Acute aortic dissection patients enrolled in the International Registry of Acute Aortic Dissection (IRAD) between 1996 and January 2007 were evaluated for factors contributing to delays in presentation to diagnosis and in diagnosis to surgery. Multiple linear regression was performed to determine relative delay time ratios (DTRs) for individual correlates. The median time from arrival at the emergency department to diagnosis was 4.3 hours (quartile 1–3, 1.5–24 hours; n=894 patients) and from diagnosis to surgery was 4.3 hours (quartile 1–3, 2.4–24 hours; n=751). Delays in acute aortic dissection diagnosis occurred in female patients; those with atypical symptoms that were not abrupt or did not include chest, back, or any pain; patients with an absence of pulse deficit or hypotension; or those who initially presented to a nontertiary care hospital (all P <0.05). The largest relative DTRs were for fever (DTR=5.11; P <0.001) and transfer from nontertiary hospital (DTR=3.34; P <0.001). Delay in time from diagnosis to surgery was associated with a history of previous cardiac surgery, presentation without abrupt or any pain, and initial presentation to a nontertiary care hospital (all P <0.001). The strongest factors associated with operative delay were prolonged time from presentation to diagnosis (DTR=1.35; P <0.001), race other than white (DTR=2.25; P <0.001), and history of coronary artery bypass surgery (DTR=2.81; P <0.001).

Conclusions—

Improved physician awareness of atypical presentations and prompt transport of acute aortic dissection patients could reduce crucial time variables.

Risk factors for diagnostic delay in acute aortic dissection

In acute aortic dissection (AAD), timely diagnosis is challenging. However, dedicated studies of the entity and determinants of delay are currently lacking. We surveyed pre-/in-hospital time to diagnosis and explored risk factors for diagnostic delay. We analyzed the dedicated database of a metropolitan AAD network (161 patients diagnosed since 1996; 115 Stanford type A) in terms of hospital arrival times (from pain to presentation at any hospital) and in-hospital diagnostic times (presentation to final diagnosis). Median (interquartile range) in-hospital diagnostic times were approximately twofold greater than hospital arrival times (177 minutes, 644, vs 75 minutes, 124, p = 0.0001, Wilcoxon test). Median annual in-hospital diagnostic times were most often approximately 3 hours (spread was wide, but decreased after 2001; rho = -0.94, p = 0.005). Risk factors (univariate analysis) for in-hospital diagnostic time >75th percentile (12 hours) included pleural effusion (odds ratio 3.96, 95% confidence interval 1.80 to 8.69), dyspneic presentation (odds ratio 3.33, 95% confidence interval 1.93 to 8.59), and age <70 years (odds ratio 2.34, 95% confidence interval 1.03 to 5.36). Systolic arterial pressure < or =105 mm Hg decreased the likelihood of lengthy diagnosis (odds ratio 0.08, 95% confidence interval 0.01 to 0.59). In patients (n = 82) with routine values (since 2000), troponin positivity (odds ratio 3.63, 95% confidence interval 1.12 to 11.84) and an acute coronary syndrome-like electrocardiogram (odds ratio 2.88, 95% confidence interval 1.01 to 8.17) were also risk factors. In conclusion, in a metropolitan setting, most of the diagnostic delay may occur in hospital. At presentation, pleural effusion, troponin positivity, acute coronary syndrome-like electrocardiogram, and dyspnea are possible "clinical confounders" associated with particularly long in-hospital diagnostic times.