Patrizia Pedrotti

Autonomic Changes Associated With Spontaneous Coronary Spasm in Patients With Variant Angina

OBJECTIVES This study sought to investigate whether changes in nervous autonomic tone may have a role in the mechanisms triggering spontaneous coronary spasm in variant angina. BACKGROUND Previous studies have suggested that both sympathetic and vagal activation may act as a trigger of epicardial artery spasm in patients with variant angina, but the actual role of autonomic changes in spontaneous coronary spasm remains unknown. METHODS We analyzed the changes in heart rate variability associated with episodes of ST segment elevation detected on Holter monitoring in 23 patients with variant angina (18 men, 5 women; mean [+/-SD] age 59 +/- 12 years). For study purposes, episodes of transmural ischemia lasting > or = 3 min and without any ST segment changes in the previous 40 min were selected for analysis. Heart rate variability indexes were calculated at 2-min intervals, at 30,15,5 and 1 min before ST elevation and at peak ST segment elevation. Ninety-three of 239 total ischemic episodes (39%) fulfilled the inclusion criteria. RESULTS The results showed that 1) high frequency (HF) (0.04 to 0.15 Hz), a heart rate variability index specific for vagal activity, decreased in the 2 min preceding ST segment elevation (p < 0.001) and returned to basal levels at peak ST segment elevation; 2) heart rate and low frequency (0.04 to 0.15 Hz), which are partially correlated with sympathetic activity, showed a significant increase at peak ST segment elevation (p < 0.001 for both); 3) the pattern of the HF reduction before ST segment elevation was consistently confirmed in several subgroups of ischemic episodes, including those of patients with or without coronary stenoses, those of patients with anterior or inferior ST segment elevation, those occurring during daily or nightly hours and silent episodes. There were no significant variations in heart rate variability in control periods selected from Holter tapes of patients and before ST segment elevation induced by balloon inflation in 20 patients undergoing coronary angioplasty. CONCLUSIONS Our data show that changes in autonomic tone are likely to contribute to trigger or predispose to epicardial spasm. In particular, although not excluding an active role for adrenergic mechanisms, our data suggest that a vagal withdrawal may often be a component of the mechanisms leading to spontaneous coronary vasospasm.

Usefulness of the Addition of Heart Rate Variability to Holter Monitoring in Predicting In-Hospital Cardiac Events in Patients With Unstable Angina Pectoris

Transient ischemia on Holter monitoring is a major determinant of outcome in unstable angina. In this study we investigated whether analysis of heart rate variability (HRV) may further improve the prognostic yield of Holter monitoring in this clinical setting. We performed 24-hour Holter monitoring in 75 patients with unstable angina (59 men, aged 62 +/- 9 years) within 12 hours of hospital admission. Number and duration of myocardial ischemic episodes, and both time domain and frequency domain HRV measures were obtained from Holter recordings. In-hospital major cardiac events (death or myocardial infarction) occurred in 7 patients (9%). Episodes of ST-segment depression on Holter monitoring were found in 6 of 7 patients (86%) with and in 26 of 68 patients (38%) without events (p <0.05). There were no differences between patients with or without events in both time domain (standard deviation [SD] of all normal RR intervals in the entire 24-hour electrocardiographic recording (SDNN), SD of the mean RR intervals for all 5-minute segments (SDANN-i), mean of SD of all RR intervals for all 5-minute segments (SDNN-i), percentage of differences between adjacent RR intervals >50 ms (pNN50), and square root of the mean squared differences of successive RR intervals) (RMSSD), and frequency domain (ultra low, very low, low, and high frequency) HRV indexes. However, the low-frequency/high-frequency (LF/HF) ratio was significantly higher in patients with cardiac events (2.12 +/- 1.4 vs 1.48 +/- 0.5, p = 0.01). Moreover, when considering only the 32 patients with myocardial ischemic episodes on Holter monitoring, the LF/HF ratio was again higher in the 6 patients with than the 26 patients without major cardiac events (2.45 +/- 1.5 vs 1.31 +/- 0.3, p <0.01). Multivariate logistic regression, including clinical and angiographic variables, showed that transient ischemia on Holter monitoring was the only independent determinant of outcome (odds ratio = 12.2, p = 0.03), with the LF/HF ratio being only slightly over statistical significance (odds ratio for 0.1 increments = 2.8, p = 0.08). Our data confirm that transient ischemia on Holter monitoring is a powerful predictor of cardiac events in unstable angina and indicates that an imbalance in cardiac autonomic tone toward a prevalence of sympathetic activity increases the risk of events in this group of patients.

Preconditioning by Transient Myocardial Ischemia Confers Protection Against Ischemia-Induced Ventricular Arrhythmias in Variant Angina

BACKGROUND In experimental models, ischemic preconditioning of the heart protects against ischemic damage and ventricular arrhythmias during subsequent coronary occlusion. In this study, we investigated whether protection against ischemic suffering and ischemia-induced arrhythmias may occur after spontaneous transmural ischemia in humans. METHODS AND RESULTS We performed 24-hour Holter monitoring in 10 patients with variant angina who developed complex ventricular arrhythmias (CVAs, more than five premature ventricular beats per minute or repetitive ventricular arrhythmias) during episodes of ST-segment elevation. A total of 150 episodes of ST-segment elevation were detected on Holter monitoring, 21 (14%) of which showed CVAs. Episodes separated from the previous one by a time interval of < or = 30 minutes or by a time interval of > 30 minutes did not differ in either magnitude or duration of ST-segment elevation, but CVAs occurred more frequently in the second group (3% versus 29%, P < .0001). The time interval from the preceding ischemic episode was longer for the episodes with compared with those without CVAs (197 +/- 275 versus 57 +/- 87 minutes, P < .001), but these two groups of episodes also had similar severities and durations of ST-segment elevation. Finally, when we analyzed 13 clusters of two to six ischemic episodes, CVAs were found much more frequently in the first (92%) than in the last (23%, P = .009) episode of the clusters, while ST-segment elevations were similar (2.1 +/- 1.6 versus 2.2 +/- 1.1 mm) and ischemia durations shorter in the first than in the last episode (3.9 +/- 3.6 versus 6.1 +/- 1.7 minutes, P = .03). CONCLUSIONS Our data indicate that preconditioning by transient ischemia induces a significant protection against ischemia-induced CVAs in patients with variant angina. This beneficial effect was not related to a reduction in either severity or duration of ischemia, suggesting that arrhythmic protection was a direct consequence of preconditioning rather than an epiphenomenon of ischemic protection.

Regional and global ventricular systolic function in isolated ventricular non-compaction: Pathophysiological insights from magnetic resonance imaging

BACKGROUND Isolated ventricular non-compaction (IVNC) is frequently, but not invariably, associated with left ventricular (LV) systolic dysfunction. Factors impacting on regional and global LV function are unknown. The aim of the study was to apply magnetic resonance imaging (MRI) to evaluate the impact of extent and severity of ventricular non-compaction on LV systolic function in patients with IVNC. METHODS Sixteen adult patients with IVNC as defined by previously validated MRI criteria [ratio between end-diastolic thickness of non-compacted and compacted myocardium (NC/C ratio)> 2.3 in ≥ 1 LV segment] were enrolled. Short-axis cine images were employed for analysis. Applying a 16-segment LV model, regional systolic performance was assessed qualitatively (wall motion score, WMS; 1 = normal, 2 = mild hypokinesia, 3 = moderate-to-severe hypokinesia, and 4 = a/dyskinesia) as well as quantitatively [fractional wall thickening, FWT (%)=100 × (end-diastolic wall thickness-end-systolic wall thickness)/end-diastolic wall thickness)]. RESULTS Mean LV ejection fraction was 43.8 ± 15.4% (range, 17-68%). Regional disease severity, as expressed by the NC/C ratio, revealed a significant correlation with WMS (r=0.26; p=0.018) and FWT (r=-0.30; p=0.006). The total number of non-compacted segments/patient (NoNC) as an index of disease extent was a significant independent correlate of LV ejection fraction by multivariate regression analysis (β=-5.24; p=0.038) and an excellent predictor of global LV dysfunction (ROC analysis, AUC=0.98; p<0.0001). CONCLUSIONS In patients with IVNC, disease severity correlates with the degree of LV dysfunction at a regional level. The extent of myocardial non-compaction is an independent predictor of global LV dysfunction.

The first Caucasian patient with p.Val122Ile mutated-transthyretin cardiac amyloidosis treated with isolated heart transplantation.

Effective treatments for mutated transthyretin (TTR)-related cardiac amyloidosis are limited. Heart transplantation or combined liver–heart transplantation are the most successful options, although results rely on underline mechanism and systemic nature of the disease. In this report, we present the first case of a Caucasian patient with the p.Val122Ile mutated TTR-related cardiac amyloidosis treated with heart transplantation due to this gene mutation frequent in Afro-Americans with a prevalent isolated heart involvement. The choice of isolated heart transplantation instead of combined heart and liver transplantations was based on (1) severe and progressive cardiac disease, (2) evidence of a gene mutation generally associated with isolated cardiac disease and (3) absence of relevant extra-cardiac involvement (with the possible exception of mild peripheral neuropathy). In any case, the very short post-transplant observation period of 10 months does not allow any conclusions on the long-term course of the presented strategy. Finally, it is the first European Caucasian family with the p.Val122Ile TTR mutation that has been described. Till now, very few Caucasian cases of p.Val122Ile mutated TTR-related cardiac amyloidosis have been reported. The patient and some members of his family also had mild peripheral neuropathy suggesting a regional phenotypic heterogeneity of European Caucasian TTR p.Val122Ile.

Non-invasive imaging of vascular inflammation

In large-vessel vasculitides, inflammatory infiltrates may cause thickening of the involved arterial vessel wall leading to progressive stenosis and occlusion. Dilatation, aneurysm formation, and thrombosis may also ensue. Activated macrophages and T lymphocytes are fundamental elements in vascular inflammation. The amount and density of the inflammatory infiltrate is directly linked to local disease activity. Additionally, patients with autoimmune disorders have an increased cardiovascular (CV) risk compared with age-matched healthy individuals as a consequence of accelerated atherosclerosis. Molecular imaging techniques targeting activated macrophages, neovascularization, or increased cellular metabolic activity can represent effective means of non-invasive detection of vascular inflammation. In the present review, novel non-invasive imaging tools that have been successfully tested in humans will be presented. These include contrast-enhanced ultrasonography, which allows detection of neovessels within the wall of inflamed arteries; contrast-enhanced CV magnetic resonance that can detect increased thickness of the arterial wall, usually associated with edema, or mural enhancement using T2 and post-contrast T1-weighted sequences, respectively; and positron emission tomography associated with radio-tracers such as [18F]-fluorodeoxyglucose and the new [11C]-PK11195 in combination with computed tomography angiography to detect activated macrophages within the vessel wall. Imaging techniques are useful in the diagnostic work-up of large- and medium-vessel vasculitides, to monitor disease activity and the response to treatments. Finally, molecular imaging targets can provide new clues about the pathogenesis and evolution of immune-mediated disorders involving arterial vessels.

Acute Myocardial Infarction and Cardiac Arrest in Atypical Takayasu Aortitis in a Young Girl Unusual Diagnostic Role of Cardiac Magnetic Resonance Imaging in Emergency Setting

A 16-year-old girl collapsed suddenly while on her way to school. When the rescue team arrived, they found her to be in asystole. Spontaneous circulation was restored after 14 minutes of cardiopulmonary resuscitation. A 12-lead electrocardiogram showed sinus tachycardia and diffuse repolarization abnormalities (Figure 1). An echocardiogram showed moderate aortic regurgitation with severely impaired left and right systolic function. Computed tomography showed increased thickness of the aortic wall extending from the sinotubular junction to the abdominal aorta (Figure 2). The arch branches, celiac trunk, and renal arteries were normal. The patient was transferred to the cardiac surgery department of our hospital. The chest radiograph showed a normal-size cardiac silhouette but with evidence of interstitial edema (Figure 3). Transesophageal echocardiography showed increased thickness of the ascending and descending aortic wall, with mild aortic regurgitation and severe depression of left and right systolic function. No intimal flap of aortic wall was evident. Six hours after the onset of symptoms, cardiac magnetic resonance imaging showed (1) severe impairment of left systolic function with left ventricular ejection fraction of 15% and akinesis of the anterolateral and apical segments (Movie I of the online-only Data Supplement) (2) moderate aortic regurgitation, (3) increased thickness of the ascending and descending aortic wall in gradient-echo steady-state free precession cine (Movie II of the online-only Data Supplement) in T2-weighted images and in delayed-enhancement images after gadolinium–diethylenetriaminepentaacetic acid contrast medium (Figure 4), (4) dilatation of the ascending aorta with extensive irregularities of the descending aortic wall in angiography (Figure 5 and Movie III of the online-only Data Supplement), (5) subendocardial delayed enhancement of the left …

Survival and Left Ventricular Function Changes in Fulminant Versus Nonfulminant Acute Myocarditis

Background: Previous reports have suggested that despite their dramatic presentation, patients with fulminant myocarditis (FM) might have better outcome than those with acute nonfulminant myocarditis (NFM). In this retrospective study, we report outcome and changes in left ventricular ejection fraction (LVEF) in a large cohort of patients with FM compared with patients with NFM. Methods: The study population consists of 187 consecutive patients admitted between May 2001 and November 2016 with a diagnosis of acute myocarditis (onset of symptoms <1 month) of whom 55 required inotropes and/or mechanical circulatory support (FM) and the remaining 132 were hemodynamically stable (NFM). We also performed a subanalysis in 130 adult patients with acute viral myocarditis and viral prodrome within 2 weeks from the onset, which includes 34 with FM and 96 with NFM. Patients with giant-cell myocarditis, eosinophilic myocarditis, or cardiac sarcoidosis and those <15 years of age were excluded from the subanalysis. Results: In the whole population (n=187), the rate of in-hospital death or heart transplantation was 25.5% versus 0% in FM versus NFM, respectively (P<0.0001). Long-term heart transplantation–free survival at 9 years was lower in FM than NFM (64.5% versus 100%, log-rank P<0.0001). Despite greater improvement in LVEF during hospitalization in FM versus NFM forms (median, 32% [interquartile range, 20%–40%] versus 3% [0%–10%], respectively; P<0.0001), the proportion of patients with LVEF <55% at last follow-up was higher in FM versus NFM (29% versus 9%; relative risk, 3.32; 95% confidence interval, 1.45–7.64, P=0.003). Similar results for survival and changes in LVEF in FM versus NFM were observed in the subgroup (n=130) with viral myocarditis. None of the patients with NFM and LVEF ≥55% at discharge had a significant decrease in LVEF at follow-up. Conclusions: Patients with FM have an increased mortality and need for heart transplantation compared with those with NFM. From a functional viewpoint, patients with FM have a more severely impaired LVEF at admission that, despite steep improvement during hospitalization, remains lower than that in patients with NFM at long-term follow-up. These findings also hold true when only the viral forms are considered and are different from previous studies showing better prognosis in FM.

Circadian variation of ischemic threshold in syndrome X

To evaluate whether the ischemic threshold has a circadian rhythm in patients with syndrome X, we analyzed 90 episodes of ST depression detected on 24-hour Holter recordings of 12 such patients. Ischemic threshold was considered as heart rate (HR) at 1 mm ST depression. To correct for differences in basal HR among patients, however, the ischemic threshold was also calculated as a normalized index of HR at 1 mm ST depression: [(HR at 1 mm ST-24-hour modal HR)/24-hour modal HR]-100. Mean hourly values of both absolute and normalized HRs at 1 mm ST depression were obtained by grouping and averaging respective values of all episodes detected in every hour of the day in all patients. Chronobiologic analysis was performed by single cosinor method. A significant circadian rhythm was found for HR (mesor 76 beats/min, amplitude 10 beats/min, acrophase at 2:16 P.M., p < 0.001), number of episodes of ST depression (mesor 3.75, amplitude 2.9, acrophase at 2:45 P.M., p < 0.001) and cumulative time of ischemia, with a high correlation of distributions. Episodes of ST depression showed a double peak initially in the morning, and again in the afternoon. Both raw and normalized values of HR at 1 mm ST depression also had a significant circadian variation in ischemic threshold, which was lower in the night and early morning hours, progressively increased until the first afternoon hours, and subsequently decreased in the evening.(ABSTRACT TRUNCATED AT 250 WORDS)

Unexpected myocarditis in thalassaemia major patient screened for iron load cardiomyopathy.

A 45-year-old white female with thalassaemia major, diabetes mellitus and hypogonadism underwent routine cardiac magnetic resonance (CMR) imaging to evaluate T2*, a myocardial and hepatic iron load indicator useful in the management of iron chelating therapy. At cardiac cine imaging, left ventricular antero-apical mild hypokinesia and pericardial effusion were evident. T2 weighted STIR …