Clinical characteristics and coronary angiographic findings of patients with unstable angina, acute myocardial infarction, and survivors of sudden ischemic death occurring during and after sport

Optical Coherence Tomography for the Diagnosis of Exercise-Related Acute Cardiovascular Events and Inconclusive Coronary Angiography

Objectives

The aim of this study is to assess the utility of optical coherence tomography (OCT) in patients with exercise-related acute coronary syndrome (ACS) presenting with inconclusive angiographic findings.

Background

Regular physical activity reduces the incidence of cardiovascular events. Nevertheless, the risk of ACS or sudden cardiac death (SCD) increases during sport. In adults older than 35 years, exercise-related ACS or SCD is associated with plaque rupture, but not infrequently patients present ambiguous angiographic findings.

Methods

Between September 2015 and January 2020, patients admitted for ACS or SCD triggered by physical exertion and with coronary stenosis ≤50% were included in this prospective observational study. OCT was performed on the artery deemed to be responsible of the event.

Results

Ten patients were enrolled, predominantly men (80%) of middle age (51 years old, IQR 41–63) with low cardiovascular risk burden. Cycling was the most frequent (50%) exercise-related trigger, 8 patients were regular sport practitioners, and 7 had the clinical event during strenuous exertion. Five patients presented with non-ST-elevation ACS, two with ST-elevation ACS, and three with SCD. Angiographic analysis showed nonsignificant stenosis in all patients (42% stenosis, IQR 36–46). OCT identified the etiology of the event in 9 patients (4 plaque erosion, 3 plaque rupture, 1 eruptive calcific nodule, and 1 coronary dissection). Treatment was adjusted according to OCT findings.

Conclusions

OCT is a valuable technique to identify the etiology of exercise-related ACS or SCD in patients with nonobstructive coronary arteries and, as a result, may lead to a more specific treatment.

Is physical activity a cause of longevity? It is not as straightforward as some would believe. A critical analysis

There are discrepant findings between (A) observational follow-ups and (B) interventional studies that investigate possible causal association between high physical activity and low mortality. Participation in vigorous physical activity at a specific time-point is an indicator of good fitness and health, and is associated with a reduced risk of death. However, neither randomised controlled trials nor experimental animal studies have provided conclusive evidence to show that physical activity started during adulthood extends lifespan. Consequently, the undisputed health-related benefits of exercise have yet to translate into any proven causal relationship with longevity. Physical activity improves fitness and physical function, and confers other health-related effects. These outcomes have a greater basis in evidence-based data than any claims of a reduced risk of death, especially when recommending physical activity for previously physically inactive middle-aged and elderly adults.

The effects of acute garlic supplementation on the fibrinolytic and vasoreactive response to exercise

Background

The purpose of this project was to examine the effects of acute garlic supplementation on fibrinolysis and vasoreactivity both at rest and following maximal exercise.

Methods

Eighteen healthy trained males (20.9 ± 2.2 years, 178 ± 7.7 cm, 75.5 ± 9.6 kg, VO₂max = 59.8 ± 6.7 ml • kg⁻¹ • min⁻¹) performed a graded treadmill test to volitional exhaustion. Blood samples were taken at rest, within two minutes post-exercise, and one hour post-exercise. Eleven of the subjects also had a brachial vasoreactivity test performed immediately after the blood sample to assess flow-mediated dilation (FMD) of the brachial artery. Participants were randomly assigned to ingest either 900 mg of powdered garlic or a placebo three hours before the exercise session. The supplement was distributed in a double-blind, crossover fashion. Participants repeated the protocol with the other treatment after a 14-day washout period. Paired t-tests were used to compare VO₂max between the two trials. A two-factor (treatment and time) repeated measures analysis of variance (ANOVA) was used to assess changes in FMD, tPA activity, tPA antigen, and PAI-1 activity. A priori statistical significance was set at P <0.05.

Results

VO₂max was greater for the garlic treatment trial vs. placebo (Placebo = 59.8 ± 6.7 ml • kg⁻¹ • min⁻¹; Garlic = 61.4 ± 6.6 ml • kg⁻¹ • min⁻¹). There was no main effect for treatment and no treatment x time interaction for FMD or any fibrinolytic variables examined.

Conclusion

Acute garlic supplementation does not alter vasoreactivity, fibrinolytic potential or the fibrinolytic response to exercise in young healthy trained males. Acute garlic supplementation does, however, cause a small but statistically significant increase in VO₂max. It remains unclear if this increase in VO₂max is of functional importance.

[Myocardial infarction related to sport. Acute clinical and coronary angiographic characteristics in 16 cases]

OBJECTIVE

Determination of clinical and angiographic characteristics of myocardial infarctions related to sport.

METHODS

Retrospective study of acute coronary syndromes with ST elevation related to sport treated with interventional cardiology from 2006 to 2013.

RESULTS

Sixteen patients were included. They are mostly men (15/16), aged 24-65 years (over 35 years old in 13 cases) with few cardiovascular risk factors, most frequently heredity or smoking. Myocardial infarctions usually occur during the practice of sports (13/16), with serious rhythmic complications in three of the cases. On angiography, most patients have single vessel disease (12/16).

CONCLUSION

Myocardial infarction related to sports affects a male population aged over 35 years old with few cardiovascular risk factors, most often single vessel disease, making the preventative screening uneasy. Other studies investigating larger populations, assessing previous clinical events (symptoms, results of stress tests), evaluating the impact of competition and integrating sudden deaths would improve the screening and the treatment of sport-related myocardial infarctions.

[Sportman's myocardial infarction]

Sport related myocardial infarctions are rare. They concern a population mainly male, of more than 35 years, with a high prevalence of smoker. The initial clinical presentation is serious, with frequent ventricular fibrillations, the mode of revelation that can be a sudden death. The angiographic data mainly shows a single vessel disease or no significant lesion. These characteristics put down the problem of the validity of preparticipation screening for cardiovascular abnormalities, and in particular the place of exercise stress testing. It is advisable to continue the reflexion to determine a reasonable strategy in the tracking of the subjects at risk. This tracking, the correction of cardiovascular risk factors, the diffusion of elementary rules good sporting practices and the management of sudden death with rapid defibrillation on the sporting sites and complexes are current measurements essential to develop.

Resolution of an intra-coronary filling defect in the proximal left anterior descending coronary artery demonstrated by 64-slice multi-detector computed tomography

The evolution of acute coronary syndromes (ACS) is not always clearly understood, and our understanding has been limited by the absence of serial information regarding the coronary vasculature in these patients. We describe a young patient with an acute inferior wall myocardial infarction in whom repeat multi-detector computed tomographic scanning (MDCT), supported by invasive studies, revealed a transient filling defect in the proximal left anterior descending coronary artery and nonobstructed circumflex and right coronary arteries. New generation 64-slice MDCT scanning provides a new method for visualizing both the coronary lumen and coronary plaque, and may prove to be a useful tool in improving our understanding of the dynamics of ACS.

Plaque instability in peripheral vessels

Vulnerable atherosclerotic plaques, those that are prone to rupture, are soft and lipid rich. Other factors that contribute to destabilizing these plaques are inflammation and vasoconstriction. Although less information is available regarding noncoronary vulnerable plaques than the more frequently studied coronary plaques, it appears that the amount of soft lipid "gruel" as well as in situ inflammation plays a crucial role in destabilizing peripheral vascular atherosclerotic plaque, eventually causing its rupture. As in the coronary circulation, it is likely that the majority of acute plaque rupture events are clinically silent. Nevertheless, preventing plaque rupture in the noncoronary circulation is of the utmost importance because this is the presumed mechanism of progression of peripheral vascular atherosclerotic lesions.

Clotting and fibrinolytic activity change during the 1 h after a submaximal run

PURPOSE

To determine the changes in clotting and fibrinolytic activity during the 1-h period after an acute submaximal exercise at a specific relative exercise intensity to ascertain whether during this time there is a greater risk for developing a clot formation or thrombus.

METHODS

Ten healthy men reported between 0700 and 1000 h and ran at 70-75% VO2max or walked at 1.2 mph for 30 min in a random counter-balanced order. Venous blood was obtained at rest, immediately after, and every 20 min during the 1-h recovery.

RESULTS

There were no differences in the resting parameters for each treatment. Walking did not alter the activity of any of the measures analyzed compared with rest. Clotting indicators activated partial thromboplastin time (APTT) was significantly decreased by approximately 2 s and remained at this level during the 1-h recovery, and factor VIII activity was elevated 66% immediately after the run and remained elevated at this level during the 1-h recovery period. Fibrinolytic indicators, t-PA, and D-dimers were significantly increased immediately after the run. However, t-PA demonstrated a quadratic negative slope during the 1-h recovery time. D-dimers remained elevated during the 1-h recovery time.

CONCLUSIONS

These results suggest that running at 70-75% VO2max resulted in elevated clotting and fibrinolytic activity. However, the clotting activity was sustained during a time when fibrinolytic activity declined, which suggests a more favorable situation for clot formation during this time after exercise.

Role of plaque rupture in acute coronary syndromes

Acute coronary syndromes are caused by plaque rupture. The conventional strategy of prevention of plaque rupture has been driven by the "lipid hypothesis"--if lipid levels are optimized to target levels, the risk of coronary events is decreased. Indeed, the hypothesis has been validated by the dramatic success of statin therapy. However, further major reductions in cardiac events is a realistic goal; various mechanistic and small clinical studies show that statins have beneficial effects in addition to their lipid-lowering properties. One of these beneficial effects is stabilization of plaque. Despite billions of dollars spent on randomized clinical trials, optimal therapy for coronary artery disease is yet to be tested. This therapy might include various combinations of the Mediterranean or low-fat diet, endothelial passivation, lipid-lowering drugs, antioxidants, antiplatelet agents and anti-inflammatory agents.

Changes in ventricular repolarization during percutaneous transluminal coronary angioplasty in humans assessed by QT interval, QT dispersion and T vector loop morphology

OBJECTIVES

Based on clinical, epidemiological, and experimental data, transient cardiac ischaemia is one of the major triggering factors of malignant ventricular arrhythmia. According to animal studies, increased dispersion of repolarization is of pathophysiological relevance in this context. Therefore we explored the impact of myocardial ischaemia during single vessel coronary angioplasty on the change in ventricular repolarization, measured by QT and JT intervals and their dispersion in the 12-lead electrocardiogram. We also assessed a novel method, the 3-dimensional T vector loop, to find out whether it was sensitive to changes in ventricular repolarization during ischaemia, and whether there was any correlation with changes in the dispersion of the QT and/or JT intervals.

DESIGN

This study was prospective with consecutive patients. Only patients in sinus rhythm and without bundle branch block were included.

SETTING

All coronary angioplasties were performed at Norrlands University Hospital, Umeå. The analysis of the material was performed at the Karolinska Hospital, Stockholm.

SUBJECTS

Twenty-nine consecutive patients went through 30 elective one-vessel percutaneous transluminal coronary angioplasty (PTCA) procedures. PTCA was performed in 10 stenoses of the left anterior descending, 10 of the left circumflex, and 10 of the right coronary artery.

INTERVENTIONS

A 12-lead electrocardiogram was recorded continuously as part of routine monitoring of the patient during PTCA and the T vector loop was calculated from the simultaneously recorded. X, Y, Z leads.

MAIN OUTCOME MEASURES

Repolarization was assessed by the QRS, QT and JT intervals as well as by the T vector loop parameters (Tarea, Tavplan, and Teigenv) before and at the end of the first occlusion during PTCA.

RESULTS

PTCA, with an average occlusion time of 171 +/- 60 s (mean +/- SD), induced ischaemia on the 12-lead electrocardiogram in 73% of cases. The overall response for the 30 procedures was a significantly increased dispersion of ventricular repolarization, both corrected and uncorrected for heart rate. QT dispersion increased by, on average, 19% from 74 +/- 35 to 88 +/- 36 ms, QTc dispersion by 27% from 71 +/- 39 to 90 +/- 42 ms, and JTc dispersion by 19% from 78 +/- 32 to 94 +/- 43 ms (P < 0.05). The T vector loop became more circular and bulgy during occlusion (all three parameters changed by between 33% and 59%). There was a significant correlation between changes in one of the T vector loop parameters (Teigenv), and changes in JT and QT dispersion in the left anterior descending group.

CONCLUSIONS

Transient ischaemia during PTCA induced significant changes in ventricular repolarization, especially during occlusion of the left anterior descending artery and resulted in a significant increase in both QT and QTc dispersion. The degree of QT dispersion was such that several patients were at risk of ventricular arrhythmia, if a proper triggering extrasystole had occurred. In addition, and as an original observation, the 3-dimensional T vector loop morphology seemed even more sensitive to coronary occlusion than QT dispersion.

Aging, physical conditioning, and exercise-induced changes in hemostatic factors and reaction products

The influence of age on training-induced changes in resting and stimulated hemostatic potential was studied in three age categories (Cat I-III; 20-30 yr, 35-45 yr, and 50-60 yr, respectively) of sedentary men before and after 12 wk of training. Coagulation, fibrinolytic activity, and activation markers (reflecting fibrin formation and degradation) were determined. Physical conditioning resulted in a more pronounced increase in von Willebrand factor (vWF) and factor VIII clotting activity (FVIII:c) in Cat I and II and a more pronounced shortening of the activated partial thromboplastin time in all categories at maximal exertion and during recovery. Enhanced increases in tissue-type plasminogen activator (t-PA) antigen and activity and single-chain (sc) urokinase-type plasminogen activator (u-PA) at maximal exercise and 5 min of recovery were observed in all age groups after training. The effects on FVIII:c, vWF, and scu-PA were most pronounced in the youngest age group (Cat I). Increases in the marker of thrombin generation were highest in Cat III; no effect was seen on thrombin-antithrombin complex, plasmin-antiplasmin complex, and D-dimer in any of the age groups. We concluded that training enhances both coagulation and fibrinolytic potential during strenuous exercise. The effect on FVIII/vWF and t-PA/u-PA is most pronounced in younger individuals, whereas thrombin formation is most pronounced in older individuals.

[Effect of physical activity on incidence of sudden cardiac death. Study of the Berlin-Reinickendorf and Berlin-Spandau population]

AIM

Our investigation examined the influence of regular physical activity and sudden extrenious situations on the incidence of sudden cardiac death (scd) in two different Berlin districts with a total population of 219,251 in the examined age-groups.

PATIENTS AND METHOD

All cases of scd which occurred outside of the hospital and were documented as been induced from ventricular fibrillation were examined over a time period of 18 months. For each case the amount of and the intensity of their regular physical activity was determined. In addition the stress of the sudden extrenious situations was survived. The study population was divided into various groups depending upon their level of regular physical activity. For each group the incidence of sudden cardiac death was determined. Then the relative risk for scd during strenuous activity compared to inactivity was determined for each group. The influence of preexisting disease was calculated.

RESULTS

77 patients with scd induced from ventricular fibrillation were included in our study. In the sedentary group we found an incidence of 4.69 scd per 10(5) person-years, in the group with a low level of regular physical activity we found an incidence of 4.25, in the group with a middle level of regular physical activity an incidence of 2.63 and in the most active group 0.92 scd per 10(5) person-years. We found the relative risk for scd during highly strenuous activity compared with inactivity to be 150 in the sedentary group as opposed to 4.0 in the most active group. The preexisting illness status of the case-groups had no influence on the outcome.

CONCLUSIONS

The results show that the risk of scd for all persons regardless of their levels of regular physical activity and their preillness status is higher during strenuous activity than during inactivity. The increase of the risk for scd during activity is the highest for persons with sedentary lifestyles, whereas the risk increase for persons with active lifestyles is minimal. The protective effect of regular physical activity for scd by far exceeds the risk increase of the actual strenuous situation.

Stenosis severity and the occurrence of ventricular ectopic activity during acute coronary occlusion during balloon angioplasty

To elucidate the incidence and determinants of early ventricular arrhythmias (VA) during acute coronary occlusion, continuous electrocardiographic, heart rate, and blood pressure recordings were performed in 152 patients during standardized balloon occlusions of significant (50% to 95%) coronary artery stenoses. A control group of 13 patients with chronic total occlusion of a coronary artery was also studied. None of them developed VA during balloon inflation in the preexisting total occlusion of the artery. Balloon occlusion of a coronary artery was associated with occurrence of ventricular ectopy in 18 patients (VA group, 12%). The VA group had milder stenosis severity (72% vs 81%, p < 0.001) than the rest of the patients, and none of them had visible collaterals to the occluded vessel. The VA group also had ST-segment deviations more often (p < 0.05) during occlusion than patients with no VA. Occlusion of the left anterior descending artery caused VA more often (p < 0.05) than occlusion of the left circumflex or right coronary artery. No clinical or hemodynamic variable or medication was associated with the occurrence of VA. In stepwise logistic regression analysis, the only significant predictors of ventricular ectopic activity were the stenosis severity and the anterior site of coronary occlusion. Even a nonstenotic plaque can be so fragile that it is prone to rupture. The present findings suggest that such an occlusion may result in electrical instability more easily than occlusion of a more advanced coronary lesion.

Comparison of coronary angiographic narrowing in stable angina pectoris, unstable angina pectoris, and in acute myocardial infarction

Coronary angiographic findings were compared in patients who presented with acute myocardial infarction (AMI, n = 75), unstable angina pectoris (UAP, n = 36), or stable angina pectoris (SAP, n = 36) for > or = 2 years without evidence of any previous acute event and with an angiogram within 2 years of the initial symptoms. Angiograms were evaluated blindly for severity, extent (depending on the percentage of each coronary segment showing atherosclerosis), and pattern (discrete, < 3 loci of narrowings involving < 50% of any segment; diffuse, anything exceeding this). Patients in the SAP group had more narrowed arteries (2.4 +/- 0.7 vs 1.3 +/- 0.6 [p < 0.02] and 1.4 +/- 0.6 [p < 0.02]), more stenoses (6.0 +/- 3.3 vs 2.1 +/- 1.5 [p < 0.01] and 2.6 +/- 1.7 [p < 0.05]) and occlusions (1.3 +/- 1.1 vs 0.7 +/- 0.6 [p = 0.05] and 0.3 +/- 0.5 [p < 0.02]), and a greater extent index (0.9 +/- 0.5 vs 0.5 +/- 0.3 [p < 0.02] and 0.5 +/- 0.3 [p < 0.02]) than those in the AMI and UAP groups. Furthermore, a discrete pattern was less prevalent in patients with UAP than in those with SAP or AMI (3% vs 40% [p < 0.02] and 25% [p < 0.05], respectively). In conclusion, patients who present with acute coronary syndromes have less extensive atherosclerosis than those who present with chronic stable angina. Therefore, in the former group, coronary atherosclerosis appears to be more susceptible to ischemic stimuli responsible for acute coronary syndromes.(ABSTRACT TRUNCATED AT 250 WORDS)

Characteristics of conditioned and sedentary men with acute coronary syndromes

To evaluate the role of habitual exertion in the development and manifestation of coronary artery disease, 36 well-conditioned men with acute coronary syndromes (4 with unstable angina, 23 with acute myocardial infarction and 9 survivors of sudden ischemic death) related to sports were compared with 36 sedentary men with the same syndromes occurring at rest. The mean age of the study subjects was 48 years (range 25 to 65). Patients exercised on average 6 hours/week (range 2 to 15) for > or = 10 years (range 10 to 45). Coronary angiography was performed within 4 hours after the onset of symptoms. The well-conditioned men had fewer risk factors than the inactive men (control subjects): fewer of them smoked (58 vs 94%, odds ratio 0.08) or had serum total cholesterol levels > or = 240 mg/dl (14 vs 56%, odds ratio 0.13, both p < 0.05). In addition, these men had less diseased (28 vs 72%, odds ratio 0.15, p < 0.02) and less severely stenotic (36 vs 78%, odds ratio 0.16, p < 0.03) coronary arteries. The association between activity levels and angiographic disease severity remained significant after correction for risk factors. Lesion morphology, site of the lesion and presence of thrombus of the culprit artery and diameter and dominance of all coronary arteries did not differ between the well-conditioned men and control subjects. This study suggests that regular strenuous exercise can reduce coronary artery disease and shows a common pathogenesis for acute coronary syndromes related and unrelated to sport.

Toward the quiescent coronary plaque

The treatment of coronary atherosclerosis requires an understanding of the pathophysiology of plaque rupture. The rupture of lipid-laden, macrophage-rich plaques initiates unstable angina, acute myocardial infarction and sudden cardiac death. Plaque rupture occurs when the circumferential tension on a plaque exceeds its tensile strength, an event that cannot be predicted by coronary angiography. The incidence of plaque rupture appears to be reduced in patients receiving cholesterol-lowering therapy, beta-adrenergic blocking agents and, possibly, angiotensin-converting enzyme inhibitors and antioxidants. Not all ruptured coronary plaques produce an acute coronary syndrome. The consequences of plaque rupture depend on the extent of thrombus formation over the fissured plaque. This is determined by flow characteristics within the vessel as well as the activity of the thrombotic and fibrinolytic systems. Recent advances in cardiovascular molecular biology, coronary diagnostic techniques and cardiac therapeutics have opened windows of opportunity to study and modify the factors leading to plaque rupture. The local modification of gene expression to alter plaque composition and to elucidate and subsequently inhibit the prothrombotic and fibrinolytic defects that promote coronary thrombosis may, in future, prevent plaque rupture and its consequences. The application of such a concerted interdisciplinary approach promises a paradigm shift in the management of coronary artery disease toward the prevention of plaque rupture and its sequelae.

Recurrent acute myocardial infarction during sport

A 48-yr-old well conditioned man developed acute myocardial infarction twice during sporting activities. After both events right coronary angiography showed a moderate proximal stenosis and, 5 months later, a subtotal obstruction at the site of prior slight lumen irregularity. This case suggests a causal relationship between sport and the occurrence of acute coronary events.