Patients with short QT syndrome (SQTS) have an increased risk for atrial tachyarrhythmias, ventricular tachyarrhythmias, and/or sudden cardiac death. PQ segment depression (PQD) is related to atrial ...fibrillation and carries a poor prognosis in the setting of acute inferior myocardial infarction and is a well-defined electrocardiographic (ECG) marker of acute pericarditis.
To evaluate the prevalence of PQD in SQTS and to analyze the association with atrial arrhythmias.
Digitalized 12-lead ECGs of SQTS patients were evaluated for PQD in all leads and for QT intervals in leads II and V5. PQD was defined as ≥0.05 mV (0.5 mm) depression from the isoelectric line.
A total of 760 leads from 64 SQTS patients (mean age 36 ± 18 years; 48 75% men) were analyzed. PQD was seen in 265 (35%) leads from 52 (81%) patients and was more frequent in leads II, V3, aVF, V4, and I (n = 43 67%, n = 30 47%, n = 27 42%, n = 25 39%, and n = 25 39%, respectively). Nine of 64 (14%) patients presented with atrial tachyarrhythmias, and all of them had PQD.
Fifty-two of 64 (81%) patients with SQTS reveal PQD. As PQD is rarely observed in healthy individuals, this ECG stigma may constitute a novel marker for SQTS in addition to a short QT interval.
Background
Catecholaminergic polymorphic ventricular tachycardia (CPVT) is a rare inherited disorder causing life-threatening arrhythmias. Long-term outcome studies of the channelopathy are limited. ...Objective
The aim of the present study was to summarize our knowledge on CPVT patients, including the clinical profile treatment approach and long-term outcome. Methods
In this single center study, we retrospectively and prospectively collected data from nine CPVT patients and analyzed them. Results
We reviewed nine patients with CPVT in seven families (22% male), with a median follow-up time of 8.6 years. Mean age at diagnosis was 26.4 12 years. Symptoms at admission were syncope (four patients) and aborted cardiac arrest (four patients). Family history of sudden cardiac death was screened in five patients. In genetic analyses, we found five patients with ryanodine type 2 receptor (
) mutations. Seven patients were treated with beta-blockers, and if symptoms persisted flecainide was added (four patients). Despite beta-blocker treatment, three patients suffered from seven adverse cardiac events. An implantable cardioverter defibrillator was implanted in seven patients (one primary, six secondary prevention). Over the follow-up period, three patients suffered from ventricular tachycardia (ten times) and five patients from ventricular fibrillation (nine times). No one died during follow-up. Conclusion
Our CPVT cohort showed a high risk of cardiac events. Family screening, optimal medical therapy and individualized treatment are necessary in affected patients in referral centers.
Zusammenfassung
Ein 17-jähriger Patienten mit ventrikulärer Extrasystolie und normaler linksventrikulärer Funktion wurde nach erfolgloser Katheterablation zur Reablation vorgestellt. Im Langzeit-EKG ...fiel eine massive, über den gesamten Tag verteilte polymorphe ventrikuläre Extrasystolie auf. Der Patient berichtete über gelegentliche Lähmungserscheinungen, in seinem Gesicht fielen weit auseinanderstehende Augen, ein tiefsitzender Ohrenansatz und eine sehr hohe Stirn auf. Diese 3 Auffälligkeiten ergaben eine Verdachtsdiagnose, die molekularbiologisch bestätigt wurde und eine völlig andere Therapiestrategie zur Folge hatte.
Patients with a short QT syndrome (SQTS) are at risk of sudden cardiac death (SCD). It is not known whether abbreviation of cardiac repolarization alters mechanical function in SQTS. Controversies ...persist regarding whether the U wave is a purely electrical or mechanoelectrical phenomenon.
The present study uses echocardiographic measurements to discriminate between the hypotheses for the origin of the U wave.
Diagnostic work-up including echocardiography and electrocardiogram was performed in 5 SQTS patients (39 +/- 19 years old) from 2 unrelated families with a history of SCD and 5 age-matched and gender-matched control subjects.
QT intervals were 268 +/- 18 ms (QTc 285 +/- 28 ms) in SQTS versus 386 +/- 20 ms (QTc 420 +/- 22 ms) in control subjects (P < .005). In SQTS patients, the end of the T wave preceded aortic valve closure by 111 +/- 30 ms versus -12 +/- 11 ms in control subjects (P < .005). The interval from aortic valve closure to the beginning of the U wave was 8 +/- 4 ms in patients and 15 +/- 11 ms in control subjects (P = .25). Thus, the inscription of the U wave in SQTS patients coincided with aortic valve closure and isovolumic relaxation, supporting the hypothesis that the U wave is related to mechanical stretch.
Our data show for the first time a significant dissociation between the ventricular repolarization and the end of mechanical systole in SQTS patients. Coincidence of the U wave with termination of mechanical systole provides support for the mechanoelectrical hypothesis for the origin of the U wave.
Patients with Brugada syndrome (BrS) and a spontaneous type 1 ECG are considered to be at greater increased risk for sudden cardiac death than are patients with an abnormal ECG only after ...administration of sodium channel blockers and therefore represent a more severe phenotype. Thus, it can be hypothesized that in the presence of a more severe electrical phenotype, structural and functional changes are more likely expected because electrical changes can play a causal role in producing structural changes.
The purpose of this study was to investigate whether the different ECG manifestations in patients with BrS are associated with structural changes detected by cardiovascular magnetic resonance imaging.
Cardiovascular magnetic resonance imaging was performed on 69 consecutive patients with proven BrS and 30 healthy controls. Twenty-six patients had a spontaneous diagnostic type 1 BrS ECG; the remainder had a type 1 response to ajmaline provocation. Left and right ventricular volumes and dimensions were assessed and compared with respect to ECG pattern.
The right ventricular outflow tract area was significantly enlarged in patients with a spontaneous type 1 ECG compared to patients with a nondiagnostic resting ECG or controls (11 cm(2), 9 cm(2), and 9 cm(2), respectively, P < .05). Patients with a spontaneous type 1 BrS ECG revealed significantly lower left ventricular ejection fraction than did patients with a nondiagnostic resting ECG and controls (56 ± 5 vs 59 ± 5 vs 60 ± 4, respectively, P < .05) and significantly lower right ventricular ejection fraction (54 ± 5 vs 59 ± 5, P = .001) as well as end-systolic volumes compared to controls (34 ± 9 mL/m(2) vs 28 ± 79 mL/m(2), P = .02).
Patients with a spontaneous type 1 BrS ECG reveal significantly functional and morphological alterations in both the left and right ventricles compared to patients with basal nondiagnostic ECG or controls.
A 17-year-old patient with premature ventricular contractions and normal left ventricular function was referred for reablation after an unsuccessful catheter ablation attempt. Holter monitoring ...demonstrated a high burden of premature ventricular contractions, present throughout the whole recording. The patient reported occasional paralytic attacks; his face had a dysmorphic appearance with a wide distance between the eyes, a caudal insertion of the ears, and a high forehead. These three features resulted in a clinical diagnosis that was confirmed by molecular biology and completely changed the therapeutic strategy.
We sought to evaluate the relation between atrial fibrillation (AF) and the extent of myocardial scarring together with left ventricular (LV) and atrial parameters assessed by late ...gadolinium-enhancement (LGE) cardiovascular magnetic resonance (CMR) in patients with hypertrophic cardiomyopathy (HCM).
AF is the most common arrhythmia in HCM. Myocardial scarring is also identified frequently in HCM. However, the impact of myocardial scarring assessed by LGE CMR on the presence of AF has not been evaluated yet.
87 HCM patients underwent LGE CMR, echocardiography and regular ECG recordings. LV function, volumes, myocardial thickness, left atrial (LA) volume and the extent of LGE, were assessed using CMR and correlated to AF. Additionally, the presence of diastolic dysfunction and mitral regurgitation were obtained by echocardiography and also correlated to AF.
Episodes of AF were documented in 37 patients (42%). Indexed LV volumes and mass were comparable between HCM patients with and without AF. However, indexed LA volume was significantly higher in HCM patients with AF than in HCM patients without AF (68 +/- 24 ml.m-2 versus 46 +/- 18 ml.m-2, p = 0.0002, respectively). The mean extent of LGE was higher in HCM patients with AF than those without AF (12.4 +/- 14.5% versus 6.0 +/- 8.6%, p = 0.02). When adjusting for age, gender and LV mass, LGE and indexed LA volume significantly correlated to AF (r = 0.34, p = 0.02 and r = 0.42, p < 0.001 respectively). By echocardiographic examination, LV diastolic dysfunction was evident in 35 (40%) patients. Mitral regurgitation greater than II was observed in 12 patients (14%). Multivariate analysis demonstrated that LA volume and presence of diastolic dysfunction were the only independent determinant of AF in HCM patients (p = 0.006, p = 0.01 respectively). Receiver operating characteristic curve analysis indicated good predictive performance of LA volume and LGE (AUC = 0.74 and 0.64 respectively) with respect to AF.
HCM patients with AF display significantly more LGE than HCM patients without AF. However, the extent of LGE is inferior to the LA size for predicting AF prevalence. LA dilation is the strongest determinant of AF in HCM patients, and is related to the extent of LGE in the LV, irrespective of LV mass.
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