James E. Muller

Background: Most people do not recognize symptoms of neurological and cardiac emergencies in a timely manner. This leads to delays in hospital arrival and reduced access to therapies that can open arteries. We created a smartphone app to help patients and families evaluate if symptoms may be high risk for stroke or heart attack (myocardial infarction, MI). The ECHAS (Emergency Call for Heart Attack and Stroke) app guides users to assess their risk through evidence-based questions and a test of weakness in one arm by evaluating finger-tapping on the smartphone. Objective: This study is an initial step in the accuracy evaluation of the app focused on sensitivity. We evaluated whether the app provides appropriate triage advice for patients with known stroke or MI symptoms in the Emergency Department. We designed this study to evaluate the sensitivity of the app, since the most dangerous output of the app would be failure to recognize the need for emergency evaluation. Specificity is also important, but the consequences of low specificity are less dangerous than those of low sensitivity. Methods: In this single-center cross-sectional study, we enrolled patients presenting with symptoms of possible stroke or MI. The ECHAS app assessment consisted of a series of evidence-based questions regarding symptoms and a test of finger-tapping speed and accuracy on the phone’s screen to detect unilateral arm weakness. The primary outcome was the sensitivity of the ECHAS app in detecting the need for ED evaluation. The secondary outcome was the sensitivity of the ECHAS app in detecting the need for hospital admission. Two independent and blinded board-certified physicians reviewed the medical record and adjudicated the appropriateness of the ED visit based on a 5-point score (ground truth). Finally, we asked patients semistructured questions about the app’s ease of use, drawbacks, and benefits. Results: We enrolled 202 patients (57 with stroke and 145 with MI). The ECHAS score was strongly correlated with the ground truth appropriateness score (Spearman correlation 0.41, P<.001). The ECHAS app had a sensitivity of 0.98 for identifying patients in whom ED evaluation was appropriate. The app had a sensitivity of 1.0 for identifying patients who were admitted to the hospital because of their ED evaluation. Patients completed an app session in an average of 111 (SD 60) seconds for the stroke pathway and 60 (SD 33) seconds for the MI pathway. Patients reported that the app was easy to use and valuable for personal emergency situations at home. Conclusions: The ECHAS app demonstrated a high sensitivity for the detection of patients who required emergency evaluation for symptoms of stroke or MI. This study supports the need for a study of specificity of the app, and then a prospective trial of the app in patients at increased risk of MI and stroke.

As humanity struggles with multiple existential threats, it is marvelous to see the editors of leading medical journals of the world united in a prescription to reduce the threat of nuclear war.¹ This advice is timely, as the ongoing war in Ukraine poses a risk of uncontrollable escalation to the use of nuclear weapons. This neglected danger to civilization is again visible, and a teachable moment has arrived.

The violence in Ukraine has increased the risk of a nuclear war. As in the past, cardiovascular health professionals must again utilize their skills in prevention to reduce this massive threat to the life and health of humanity.

Atherosclerotic plaques prone to rupture may cause acute myocardial infarction (MI) but can also heal without causing an event. Certain common histopathological features, including inflammation, a thin fibrous cap, positive remodelling, a large necrotic core, microcalcification, and plaque haemorrhage are commonly found in plaques causing an acute event. Recent advances in imaging techniques have made it possible to detect not only luminal stenosis and overall coronary atherosclerosis burden but also to identify such adverse plaque characteristics. However, the predictive value of identifying individual adverse atherosclerotic plaques for future events has remained poor. In this Position Paper, the relationship between vulnerable plaque imaging and MI is addressed, mainly for non-invasive assessments but also for invasive imaging of adverse plaques in patients undergoing invasive coronary angiography. Dynamic changes in atherosclerotic plaque development and composition may indicate that an adverse plaque phenotype should be considered at the patient level rather than for individual plaques. Imaging of adverse plaque burden throughout the coronary vascular tree, in combination with biomarkers and biomechanical parameters, therefore holds promise for identifying subjects at increased risk of MI and for guiding medical and invasive treatment.

Despite advanced understanding of the biology of atherosclerosis, coronary heart disease remains the leading cause of death worldwide. Progress has been challenging as half of the individuals who suffer sudden cardiac death do not experience premonitory symptoms. Furthermore, it is well-recognized that also a plaque that does not cause a haemodynamically significant stenosis can trigger a sudden cardiac event, yet the majority of ruptured or eroded plaques remain clinically silent. In the past 30 years since the term ‘vulnerable plaque’ was introduced, there have been major advances in the understanding of plaque pathogenesis and pathophysiology, shifting from pursuing features of ‘vulnerability’ of a specific lesion to the more comprehensive goal of identifying patient ‘cardiovascular vulnerability’. It has been also recognized that aside a thin-capped, lipid-rich plaque associated with plaque rupture, acute coronary syndromes (ACS) are also caused by plaque erosion underlying between 25% and 60% of ACS nowadays, by calcified nodule or by functional coronary alterations. While there have been advances in preventive strategies and in pharmacotherapy, with improved agents to reduce cholesterol, thrombosis, and inflammation, events continue to occur in patients receiving optimal medical treatment. Although at present the positive predictive value of imaging precursors of the culprit plaques remains too low for clinical relevance, improving coronary plaque imaging may be instrumental in guiding pharmacotherapy intensity and could facilitate optimal allocation of novel, more aggressive, and costly treatment strategies. Recent technical and diagnostic advances justify continuation of interdisciplinary research efforts to improve cardiovascular prognosis by both systemic and ‘local’ diagnostics and therapies. The present state-of-the-art document aims to present and critically appraise the latest evidence, developments, and future perspectives in detection, prevention, and treatment of ‘high-risk’ plaques occurring in ‘vulnerable’ patients.

Intracoronary near-infrared spectroscopy (NIRS) in ST-segment elevation myocardial infarction (STEMI) has demonstrated substantial lipid in STEMI culprit plaques. Thrombus aspiration during primary PCI reduces distal embolization and improves reperfusion. This study was performed to examine if aspiration thrombectomy reduces the lipid content of acute coronary syndrome (ACS) culprit plaques. NIRS-IVUS imaging was performed in patients with an ACS at two hospitals in the US and Sweden. After establishment of TIMI 3 flow with an undersized balloon, NIRS was performed, followed by aspiration thrombectomy, followed by repeated NIRS. The same culprit segment was identified on the post-aspiration chemogram. The culprit lipid content was quantified before and after thrombectomy as the lipid core burden index (LCBI). Aspirates were examined by histological staining for lipids, calcium, and macrophages. In 18 ACS patients (age 65 ± 11, 61% male), culprit lesions were characterized by high lipid content prior to aspiration thrombectomy. Thrombectomy resulted in a 28% reduction in culprit lesion lipid content (pre-aspiration LCBI 466 ± 141 vs. post-aspiration 335 ± 117, P = 0.0001). In addition to thrombus, histological analysis of aspirates demonstrated the presence of lipids, calcium, and macrophages, indicating that fragments of atherosclerotic plaques had been aspirated. Thrombectomy aspirates both thrombus and lipid-rich fragments of the culprit atherosclerotic plaques, thereby reducing material that may embolize during stenting. Reduction of lipid content before stenting might contribute to the beneficial effects of thrombectomy and may be particularly useful if a large lipid core is present at the culprit site.