Machine learning-based prediction of in-hospital death for patients with takotsubo syndrome: The InterTAK-ML model

AIMS

Takotsubo syndrome (TTS) is associated with a substantial rate of adverse events. We sought to design a machine learning (ML)-based model to predict the risk of in-hospital death and to perform a clustering of TTS patients to identify different risk profiles.

METHODS AND RESULTS

A ridge logistic regression-based ML model for predicting in-hospital death was developed on 3482 TTS patients from the International Takotsubo (InterTAK) Registry, randomly split in a train and an internal validation cohort (75% and 25% of the sample size, respectively) and evaluated in an external validation cohort (1037 patients). Thirty-one clinically relevant variables were included in the prediction model. Model performance represented the primary endpoint and was assessed according to area under the curve (AUC), sensitivity and specificity. As secondary endpoint, a K-medoids clustering algorithm was designed to stratify patients into phenotypic groups based on the 10 most relevant features emerging from the main model. The overall incidence of in-hospital death was 5.2%. The InterTAK-ML model showed an AUC of 0.89 (0.85-0.92), a sensitivity of 0.85 (0.78-0.95) and a specificity of 0.76 (0.74-0.79) in the internal validation cohort and an AUC of 0.82 (0.73-0.91), a sensitivity of 0.74 (0.61-0.87) and a specificity of 0.79 (0.77-0.81) in the external cohort for in-hospital death prediction. By exploiting the 10 variables showing the highest feature importance, TTS patients were clustered into six groups associated with different risks of in-hospital death (28.8% vs. 15.5% vs. 5.4% vs. 1.0.8% vs. 0.5%) which were consistent also in the external cohort.

CONCLUSION

A ML-based approach for the identification of TTS patients at risk of adverse short-term prognosis is feasible and effective. The InterTAK-ML model showed unprecedented discriminative capability for the prediction of in-hospital death.

Post-acute phase and sequelae management of epidermal necrolysis: an international, multidisciplinary DELPHI-based consensus

BACKGROUND

Long-term sequelae are frequent and often disabling after epidermal necrolysis (Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN)). However, consensus on the modalities of management of these sequelae is lacking.

OBJECTIVES

We conducted an international multicentric DELPHI exercise to establish a multidisciplinary expert consensus to standardize recommendations regarding management of SJS/TEN sequelae.

METHODS

Participants were sent a survey via the online tool "Survey Monkey" consisting of 54 statements organized into 8 topics: general recommendations, professionals involved, skin, oral mucosa and teeth, eyes, genital area, mental health, and allergy workup. Participants evaluated the level of appropriateness of each statement on a scale of 1 (extremely inappropriate) to 9 (extremely appropriate). Results were analyzed according to the RAND/UCLA Appropriateness Method.

RESULTS

Fifty-two healthcare professionals participated. After the first round, a consensus was obtained for 100% of 54 initially proposed statements (disagreement index < 1). Among them, 50 statements were agreed upon as 'appropriate'; four statements were considered 'uncertain', and ultimately finally discarded.

CONCLUSIONS

Our DELPHI-based expert consensus should help guide physicians in conducting a prolonged multidisciplinary follow-up of sequelae in SJS-TEN.

Impact of Atrial Fibrillation on Outcome in Takotsubo Syndrome: Data From the International Takotsubo Registry

Background

Atrial fibrillation (AF) is a major risk factor for mortality. The prevalence, clinical correlates, and prognostic impact of AF in Takotsubo syndrome (TTS) have not yet been investigated in a large patient cohort. This study aimed to investigate the prevalence, clinical correlates, and prognostic impact of AF in patients with TTS.

Methods and Results

Patients with TTS were enrolled from the International Takotsubo Registry, which is a multinational network with 26 participating centers in Europe and the United States. Patients were dichotomized according to the presence or absence of AF at the time of admission. Of 1584 patients with TTS, 112 (7.1%) had AF. The mean age was higher (P<0.001), and there were fewer women (P=0.046) in the AF than in the non‐AF group. Left ventricular ejection fraction was significantly lower (P=0.001), and cardiogenic shock was more often observed (P<0.001) in the AF group. Both in‐hospital (P<0.001) and long‐term mortality (P<0.001) were higher in the AF group. Multivariable Cox regression analysis revealed that AF was independently associated with higher long‐term mortality (hazard ratio, 2.31; 95% CI, 1.50–3.55; P<0.001). Among patients with AF on admission, 42% had no known history of AF before the acute TTS event, and such patients had comparable in‐hospital and long‐term outcomes compared with those with a history of AF.

Conclusions

In patients presenting with TTS, AF on admission is significantly associated with increased in‐hospital and long‐term mortality rates. Whether antiarrhythmics and/or cardioversion are beneficial in TTS with AF should thus be tested in a future trial.

Registration

URL: https://www.clinicaltrials.gov; Unique identifier: NCT01947621.

Prognostic impact of acute pulmonary triggers in patients with takotsubo syndrome: new insights from the International Takotsubo Registry

AIMS

Acute pulmonary disorders are known physical triggers of takotsubo syndrome (TTS). This study aimed to investigate prevalence of acute pulmonary triggers in patients with TTS and their impact on outcomes.

METHODS AND RESULTS

Patients with TTS were enrolled from the International Takotsubo Registry and screened for triggering factors and comorbidities. Patients were categorized into three groups (acute pulmonary trigger, chronic lung disease, and no lung disease) to compare clinical characteristics and outcomes. Of the 1670 included patients with TTS, 123 (7%) were identified with an acute pulmonary trigger, and 194 (12%) had a known history of chronic lung disease. The incidence of cardiogenic shock was highest in patients with an acute pulmonary trigger compared with those with chronic lung disease or without lung disease (17% vs. 10% vs. 9%, P = 0.017). In-hospital mortality was also higher in patients with an acute pulmonary trigger than in the other two groups, although not significantly (5.7% vs. 1.5% vs. 4.2%, P = 0.13). Survival analysis demonstrated that patients with an acute pulmonary trigger had the worst long-term outcome (P = 0.002). The presence of an acute pulmonary trigger was independently associated with worse long-term mortality (hazard ratio 2.12, 95% confidence interval 1.33-3.38; P = 0.002).

CONCLUSIONS

The present study demonstrates that TTS is related to acute pulmonary triggers in 7% of all TTS patients, which accounts for 21% of patients with physical triggers. The presence of acute pulmonary trigger is associated with a severe in-hospital course and a worse long-term outcome.

Bioprosthetic or native aortic scallop intentional laceration to prevent iatrogenic coronary artery obstruction technique in transcatheter aortic valve-in-valve procedures: a single-center initial experience

AIM

To describe six cases using the bioprosthetic or native aortic scallop intentional laceration to prevent iatrogenic coronary artery obstruction technique to prevent coronary artery obstruction during transcatheter aortic valve-in-valve procedures.

METHODS

All patients presented degeneration of a bovine pericardium bioprosthesis [four Trifecta (19, 21, 23, and 25 mm); two Mitroflow (25 and 27 mm)] resulting in severe aortic stenosis (n = 5) or severe aortic regurgitation (n = 1). Procedures were performed under fluoroscopic and echocardiography guidance, and the transfemoral access was used to deliver a self-expanding valve. Data are expressed as frequency or median (Q1-Q3).

RESULTS

Age, EuroScore II, and Society of Thoracic Surgeons score were 81 years (75-83.2), 2.9% (2.6-10.7), and 2.7% (2.3-3.2), respectively. Median left and right coronary heights were 9.1 mm (6.2-10.3) and 12.4 mm (10-13.5), respectively, with a median virtual transcatheter heart valve-to-coronary distance of 2.9 mm on the left and 4.6 mm on the right side. Isolated left leaflet laceration was planned in four patients, and bileaflet in two. One unsuccessful right leaflet laceration was reported, corresponding to the first patient (success rate 87.5%). All other seven leaflets lacerations were successfully performed, with no intraprocedure complications. No coronary obstruction, in-hospital death, valve complication, cardiovascular event, or pacemaker implantation were reported. All patients are being followed in routine outpatient visits, and no adverse events were registered.

CONCLUSION

The high procedural success and low complication rate reported in this initial experience, demonstrates that the bioprosthetic or native aortic scallop intentional laceration to prevent iatrogenic coronary artery obstruction technique can be a viable solution to prevent coronary obstruction in selected patients undergoing valve-in-valve procedures. Operator experience, periprocedural imaging and teamwork are essential to enable an accurate and successful procedure.

Age-Related Variations in Takotsubo Syndrome

BACKGROUND

Takotsubo syndrome (TTS) occurs predominantly in post-menopausal women but is also found in younger patients.

OBJECTIVES

This study aimed to investigate age-related differences in TTS.

METHODS

Patients diagnosed with TTS and enrolled in the International Takotsubo Registry between January 2011 and February 2017 were included in this analysis and were stratified by age (younger: ≤50 years, middle-age: 51 to 74 years, elderly: ≥75 years). Baseline characteristics, hospital course, as well as short- and long-term mortality were compared among groups.

RESULTS

Of 2,098 TTS patients, 242 (11.5%) patients were ≤50 years of age, 1,194 (56.9%) were 51 to 74 years of age, and 662 (31.6%) were ≥75 years of age. Younger patients were more often men (12.4% vs. 10.9% vs. 6.3%; p = 0.002) and had an increased prevalence of acute neurological (16.3% vs. 8.4% vs. 8.8%; p = 0.001) or psychiatric disorders (14.1% vs. 10.3% vs. 5.6%; p < 0.001) compared with middle-aged and elderly TTS patients. Furthermore, younger patients had more often cardiogenic shock (15.3% vs. 9.1% vs. 8.1%; p = 0.004) and had a numerically higher in-hospital mortality (6.6% vs. 3.6% vs. 5.1%; p = 0.07). At multivariable analysis, younger (odds ratio: 1.60; 95% confidence interval: 0.86 to 3.01; p = 0.14) and older age (odds ratio: 1.09; 95% confidence interval: 0.66 to 1.80; p = 0.75) were not independently associated with in-hospital mortality using the middle-aged group as a reference. There were no differences in 60-day mortality rates among groups.

CONCLUSIONS

A substantial proportion of TTS patients are younger than 50 years of age. TTS is associated with severe complications requiring intensive care, particularly in younger patients.

Using coronary CT angiography for guiding invasive coronary angiography: potential role to reduce intraprocedural radiation exposure

OBJECTIVES

We investigated the potential reduction of patient exposure during invasive coronary angiography (ICA) if the procedure had only been directed to the vessel with at least one ≥ 50% stenosis as described in the CT report.

METHODS

Dose reports of 61 patients referred to ICA because of at least one ≥ 50% stenosis on coronary CT angiography (CCTA) were included. Dose-area product (DAP) was documented separately for left (LCA) and right coronary arteries (RCA) by summing up the single DAP for each angiographic projection. The study population was subdivided as follows: coronary intervention of LCA (group 1) or RCA (group 2) only, or of both vessels (group 3), or further bypass grafting (group 4), or no further intervention (group 5).

RESULTS

57.4% of the study population could have benefitted from reduced exposure if catheterization had been directly guided to the vessel of interest as described on CCTA. Mean relative DAP reductions were as follows: group 1 (n = 18), 11.2%; group 2 (n = 2), 40.3%; group 3 (n = 10), 0%; group 4 (n = 3), 0%; group 5 (n = 28), 28.8%.

CONCLUSIONS

Directing ICA to the vessel with stenosis as described on CCTA would reduce intraprocedural patient exposure substantially, especially for patients with single-vessel stenosis.

KEY POINTS

• Patients with CAD can benefit from decreased radiation exposure during coronary angiography. • ICA should be directed solely to significant stenoses as described on CCTA. • Severely calcified plaques remain a limitation of CCTA leading to unnecessary ICA referrals.

Prevalence of severely impaired left ventricular ejection fraction after reperfused ST-elevation myocardial infarction

BACKGROUND

Preventive implantation of an implantable cardioverter defibrillator (ICD) early after myocardial infarction failed to demonstrate a survival benefit in patients with depressed left ventricular ejection fraction (LVEF). This may be explained by early recovery of the LVEF after percutaneous coronary intervention (PCI). We sought to determine the incidence of a sustained LVEF ≤35% in patients with severely depressed LVEF early after a revascularised acute ST-segment elevation myocardial infarction (STEMI).

METHODS

LVEF was assessed in patients with an acute STEMI treated with PCI in two Swiss high-volume centres within 10 days (in-hospital LVEF) after the STEMI. Those with an in-hospital LVEF ≤35% were scheduled for follow-up LVEF measurement within 6-8 weeks.

RESULTS

A total of 330 patients were included (79% male, mean age 63 ± 12 years). In-hospital LVEF measured 3 ± 3 days after STEMI was ≤35% in 32/330 patients (10%, 95% confidence interval (CI) 13%-67%). LVEF was available in 31/32 (97%) patients at follow-up 53 ± 19 days after STEMI and improved to >35% in 19 patients (61%, 95% CI 42%-78%). The incidence of a LVEF ≤35% at follow-up was 39% (12/31, 95% CI 22%-56%).

CONCLUSION

Our data demonstrate that the incidence of severely impaired LV function 53 ± 19 days after a STEMI treated with PCI is low. A severely depressed LVEF early after STEMI was present in 10% of all patients. Only 39% of these patients had a persistently impaired LVEF during follow-up. These findings support an expectant strategy before considering primary preventive ICD implantation after STEMI.

Clinical characteristics, sex hormones, and long-term follow-up in Swiss postmenopausal women presenting with Takotsubo cardiomyopathy

BACKGROUND

The overwhelming majority of patients with stress cardiomyopathy (SC) are postmenopausal women, suggesting an important pathophysiologic role of the female sex hormones. Preliminary data suggest that myocardial stunning might be provoked by estrogen deficiency.

HYPOTHESIS

We hypothesized that, compared with age- and gender-matched patients with myocardial infarction (MI) or patients with normal coronary arteries, patients with SC would exhibit altered levels of sex hormones. Furthermore, we aimed to describe the clinical course and the pattern of sex hormones of the SC patients during long-term follow-up.

METHODS

Blood samples obtained on hospital admission were analyzed for estradiol (E2), progesterone (P), luteinizing hormone (LH), and follicle-stimulating hormone (FSH) in women with SC (n = 17), age-matched women with acute MI (n = 16), and women with normal coronary arteries (n = 15). Six years after the initial event, SC patients underwent a clinical and echocardiographic follow-up and reassessment of sex hormones.

RESULTS

Estrogen concentrations at hospital admission were significantly higher in the SC group compared with the MI and the control groups, with no difference in P, FSH, and LH concentrations. Follow-up E2 after 6 years in SC patients was lower than during the acute SC episode. Follow-up P in these patients was lower than P in the MI and control groups during the acute event, with a similar trend for E2. After a median follow-up of 6.4 years, 1 sudden cardiac death occurred and 2 patients suffered from SC recurrence.

CONCLUSIONS

During the acute event, E2 concentrations are elevated in postmenopausal SC patients compared with women with acute MI or with normal coronary arteries. The higher E2 concentrations might have exerted atheroprotective effects and thus diverted the stress response to SC rather than MI. Recurrence and/or sudden cardiac death remains a potential risk of SC.

Benefit of outpatient cardiac rehabilitation in under-represented patient subgroups

OBJECTIVE

To assess the effect of outpatient cardiac rehabilitation in important patient subgroups.

DESIGN

Prospective cohort study.

SUBJECTS

Consecutive patients from March 1999 until July 2003.

METHODS

This study assessed the results of symptom-limited bicycle stress testing and health-related quality of life (Profil der Lebensqualität Chronisch Kranker) at baseline and after a 3-month rehabilitation program, and complications and drop-outs during outpatient cardiac rehabilitation.

RESULTS

Of 1061 patients, 155 (15%) women, 87 (8%) men aged >or= 75 years, 162 (15%) had diabetes mellitus and 88 (8%) did not speak the local language. Reasons for outpatient cardiac rehabilitation included acute coronary artery disease (87%), valvular heart disease (9%) and congestive heart failure (1%). Mean age was 62 years (standard deviation 11). Patients increased both their age- and body-weight-adjusted workload (p < 0.0001) and quality of life (p < 0.0001) during the program. Although the initial workload achieved was lower than for normal patients (p < 0.0001), it increased in all subgroups during outpatient cardiac rehabilitation (p < 0.0001). Baseline quality of life was lower in women, but increased in most dimensions for all subgroups assessed.

CONCLUSION

Important subgroups, such as women, elderly men, diabetic patients and ethnic minorities, are under-represented in outpatient cardiac rehabilitation, although they benefit similarly to other patients. Due to lower baseline quality of life, women may need special medical attention prior to outpatient cardiac rehabilitation.

[18F-fluorodeoxyglucose positron emission tomography in colorectal cancer: value in primary staging and follow-up]

Positron emission tomography using 18F-fluorodeoxyglucose (FDG-PET) is a encouraging imaging technique allowing a highly sensitive whole-body search for malignant foci detected by their increased glucose metabolism compared with benign tissues. Several studies are now available that indicate its added value for diagnosis and staging of colorectal cancer. In all, patient management seems to be changed in 20-30% of patients who undergo Fluorodeoxyglucose positron emission tomography in addition to standard staging procedures. Fluorodeoxyglucose positron emission tomography is also useful in monitoring radiation therapy and chemotherapy. Regarding preoperative staging of primary colorectal cancer the literature is very limited.

[F-18 fluorodeoxyglucose positron emission tomography in colorectal carcinoma]

Whole-body positron emission tomography (PET) with the radiolabeled glucose analog F-18-fluorodeoxyglucose (F-18-FDG) is a sensitive diagnostic tool that images tumors based on increased uptake of glucose. Several recent publications have shown that F-18-fluorodeoxyglucose-positron emission tomography is more sensitive than computed-tomography (CT) in detecting colorectal cancer. In patients with increasing CEA (carcinoembryonic antigen) and no evidence of recurrent disease on CT F-18-fluorodeoxyglucose-positron emission tomography often detects recurrent cancer. In all, patient management seems to be changed in about 25% of patients who undergo F-18-fluorodeoxyglucose-positron emission tomography in addition to standard staging procedure. Limited reports to date on both chemotherapy and radiotherapy support the role of F-18-fluorodexyglucose-positron emission tomography in assessing treatment response. Also regarding preoperative staging of primary colorectal cancer the literature is very limited.

[The value of F-18 fluorodeoxyglucose in positron emission tomography diagnosis of breast carcinoma]

Fluorodeoxyglucose-positron emission tomography (F-18-FDG-PET) has become an important issue in the diagnosis of malignant tumors within the last years. In breast cancer PET has been established in the diagnosis of the primary tumor as well as in recurrences with a sensitivity of 90% and a specificity of 75%-100%; additional a sensitivity of more than 90% and a specificity of about 75% is also seen in axillary lymph nodes detection. With our own results we were able to prove sensitivity of positron emission tomography in diagnosing the primary lesion, locoregional lymph nodes and the staging of metastases. Furthermore, positron emission tomography seems to be superior to conventional imaging modalities in staging primary and recurrent breast cancer, distant metastases and lymph nodes outside the axilla.