Acute pulmonary embolism pretest probability estimation by d-dimer test, our modified, new ECG score and clinical prediction rules.

Objectives: We investigated whether a sufficiently sensitive D-dimer test could exclude acute pulmonary embolism (acPE) as a stand-alone diagnostic test and compared our previously published, modified ECG score with the Wells and Geneva scores in the estimation of acPE pretest probability.

Methods: We retrospectively evaluated 345 patients who underwent chest CT angiography (CTA) for the suspicion of acPE. The pretest probability of acPE was assessed in 120 D-dimer negative [DD (-)] and 225 D-dimer positive [DD (+)] patients.

A Comparative Study of the Rapid (I) and Slow (I) Delayed Rectifier Potassium Currents in Undiseased Human, Dog, Rabbit, and Guinea Pig Cardiac Ventricular Preparations.

To understand the large inter-species variations in drug effects on repolarization, the properties of the rapid (I) and the slow (I) components of the delayed rectifier potassium currents were compared in myocytes isolated from undiseased human donor (HM), dog (DM), rabbit (RM) and guinea pig (GM) ventricles by applying the patch clamp and conventional microelectrode techniques at 37 °C. The amplitude of the E-4031-sensitive I tail current measured at -40 mV after a 1 s long test pulse of 20 mV, which was very similar in HM and DM but significant larger in RM and GM. The L-735,821-sensitive I tail current was considerably larger in GM than in RM.

Cardiac Sarcoidosis: A Comprehensive Clinical Review.

Sarcoidosis is an inflammatory multisystemic disease of unknown etiology characterized by the formation of non-caseating granulomas. Sarcoidosis can affect any organ, predominantly the lungs, lymphatic system, skin and eyes. While 90% of patients with sarcoidosis have lung involvement, an estimated 5% of patients with sarcoidosis have clinically manifest cardiac sarcoidosis (CS), whereas approximately 25% have asymptomatic, clinically silent cardiac involvement verified by autopsy or imaging studies.

New Pacing Techniques and Non-Invasive Methods That May Improve Response to Cardiac Resynchronization Therapy.

Although cardiac resynchronization therapy (CRT) is an evidence-based effective therapy of symptomatic heart failure with reduced ejection fraction (HFrEF), refractory to optimal medical treatment and associated with intraventricular conduction disturbance, the non-response rate to CRT is still around 30% [...

Novel electrocardiographic criteria may render possible the more accurate recognition of cardiac amyloidosis.

Aims: The early diagnosis of cardiac amyloidosis (CA) is paramount, since there are effective therapies that improve patient survival. The diagnostic accuracy of classical electrocardiographic (ECG) signs, such as low voltage, pseudoinfarct pattern, and conduction disturbances in the diagnosis of CA, is inferior to that of the echocardiographic myocardial deformation criteria; therefore, our aim was to find more accurate novel ECG criteria for this purpose.

Methods: We tested the diagnostic value of five novel ECG criteria, two of them devised by us, in 34 patients with confirmed CA (20 transthyretin amyloidosis and 14 AL amyloidosis) and 45 control patients with left ventricular hypertrophy on echocardiography due to hypertension, valvular aortic stenosis and hypertrophic cardiomyopathy.

The Application of a New, Modified Algorithm for the Differentiation of Regular Ventricular and Pre-Excited Tachycardias.

Background: The three-step Brugada group algorithm is the only published electrocardiographical (ECG) algorithm for differentiating ventricular tachycardia (VT) from pre-excited tachycardia (PXT) as a cause of regular wide QRS complex tachycardia (WCT). This study aimed to improve the diagnostic accuracy of the Brugada group algorithm.

Methods: This study modified the Brugada group algorithm by adding a new aVR lead criterion (initial positive deflection in lead aVR and the QRS complex area above the baseline is greater than the area below the baseline).

Cardiac sarcoidosis completely mimicking biventricular arrhythmogenic cardiomyopathy.

Cardiac sarcoidosis (CS) is a chameleon of cardiology, and it can mimic different cardiac diseases; among them is arrhythmogenic cardiomyopathy (ACM). We admitted a 70-year-old female patient with heart failure symptoms in 2015, who fulfilled all major ECG and non-invasive imaging criteria of biventricular ACM. She was well with the recommended medications for 3 years, showing only isolated cardiac involvement, but in 2018, cervical and mediastinal lymphadenopathy appeared and cervical lymph node core biopsy histology, bronchoalveolar lavage flow cytometry strongly suggested extracardiac sarcoidosis.

Novel electrocardiographic dyssynchrony criteria that may improve patient selection for cardiac resynchronization therapy.

Cardiac resynchronization therapy (CRT) is an evidence-based effective therapy of symptomatic heart failure with reduced ejection fraction refractory to optimal medical treatment associated with intraventricular conduction disturbance, that results in electrical dyssynchrony and further deterioration of systolic ventricular function. However, the non-response rate to CRT is still 20%-40%, which can be decreased by better patient selection. The main determinant of CRT outcome is the presence or absence of significant ventricular dyssynchrony and the ability of the applied CRT technique to eliminate it.

A different cardiac resynchronization therapy technique might be needed in some patients with nonspecific intraventricular conduction disturbance pattern.

Background: Current cardiac resynchronization therapy (CRT), devised to eliminate dyssynchrony in left bundle branch block (LBBB), works by pacing the latest activated left ventricular site (LALVS). We hypothesized that patients with nonspecific intraventricular conduction disturbance (NICD) pattern respond less favorably to CRT, because their LALVS is far away from that in LBBB.

Methods: By measuring the amplitude and polarity of secondary ST-segment alterations in two optional frontal and horizontal surface electrocardiogram (ECG) leads and using a software, we determined the resultant 3D spatial secondary ST vector, which is directed 180 away from the LALVS, in 110 patients with LBBB pattern and 77 patients with NICD pattern and heart failure.

Usefulness of a Novel Electrocardiographic Score to Estimate the Pre-Test Probability of Acute Pulmonary Embolism.

According to our experience the 12-lead electrocardiogram (ECG) may be used to estimate the pretest probability of acute pulmonary embolism (acPE). To this end, we devised a novel ECG score (nECGs) composed of 5 known ECG criteria, best characterizing the key pathogenetic steps of acPE. A retrospective derivation cohort including 136 patients with acPE and a prospective validation cohort including 149 consecutive patients were used to devise and validate the nECGs.

How are ECG parameters related to cardiac magnetic resonance images? Electrocardiographic predictors of left ventricular hypertrophy and myocardial fibrosis in hypertrophic cardiomyopathy.

Background: Structural myocardial changes in hypertrophic cardiomyopathy (HCM) are associated with different abnormalities on electrocardiographs (ECGs). The diagnostic value of the ECG voltage criteria used to screen for left ventricular hypertrophy (LVH) may depend on the presence and degree of myocardial fibrosis. Fibrosis can cause other changes in ECG parameters, such as pathological Q waves, fragmented QRS (fQRS), or repolarization abnormalities.

Novel electrocardiographic dyssynchrony criteria improve patient selection for cardiac resynchronization therapy.

Aims: We hypothesized that the greater the intra- or interventricular dyssynchrony (intraD, interD), the more effective cardiac resynchronization therapy (CRT) is. We sought to improve patient selection for CRT by using novel ECG dyssynchrony criteria.

Methods And Results: Left ventricular (LV) intraD was estimated by the absolute time difference between the intrinsicoid deflections (ID) in leads aVL and aVF divided by the QRS duration (QRSd): [aVLID - aVFID]/QRSd (%).

The role of electrocardiography in the elaboration of a new paradigm in cardiac resynchronization therapy for patients with nonspecific intraventricular conduction disturbance.

Cardiac resynchronization therapy (CRT) is associated with a favorable outcome only in patients with left bundle branch block (LBBB) pattern and in patients with a QRS duration > 150 ms, in patients with non-LBBB pattern with a QRS duration of 120-150 ms usually is not beneficial. After adjusting for QRS duration, QRS morphology was no longer a determinant of the clinical response to CRT. In contrast to the mainstream view, we hypothesized that the unfavorable CRT outcome in patients with non-LBBB and a QRS duration of 120-150 ms is not due to the QRS morphology itself, but to less dyssynchrony and unfavorable patient characteristics in this subgroup, such as more ischemic etiology and greater prevalence of male patients compared with patients with LBBB pattern.

Genetic predisposition in patients with hypertension and normal ejection fraction to oxidative stress.

The role of oxidative stress (OXS) due to myocardial nitric oxide synthase (NOS) uncoupling related to oxidative depletion of its cofactor tetrahydrobiopterin (BH4) emerged in the pathogenesis of heart failure with preserved ejection fraction. We determined the prevalence of six single nucleotide polymorphisms (SNPs) of genes encoding enzymes related to OXS, BH4 metabolism, and NOS function in ≥60-year-old 94 patients with hypertension and 18 age-matched controls with normal ejection fraction. Using echocardiography, 56/94 (60%) patients with hypertension had left ventricular (LV) diastolic dysfunction (HTDD+ group) and 38/94 (40%) patients had normal LV diastolic function (HTDD- group).

[The role of oxidative stress in amiodaron toxicity, in left ventricular dysfunction of hypertensive patients and in heart failure with preserved ejection fraction].

The author briefly summarizes his scientific work investigating the role of oxidative stress in cardiovascular disorders. Using in vitro biochemical, biophysical and in vivo animal research it was found that oxidative stress plays a substantial role in the pathogenesis of amiodarone toxicity and antioxidants co-administered with amiodarone exert at least partial protective effect on amiodarone toxicity, while antioxidants did not diminish and perhaps even enhanced the antiarrhythmic action of amiodarone. Thus, co-administration of antioxidants with amiodarone may lead to the more widespread application of amiodarone, which is currently the most potent available antiarrhythmic agent, but its clinical use is limited due the potentially severe toxic effect In hypertensive patients with normal ejection fraction, the most common precursor condition of heart failure with preserved ejection fraction, the potential primary causal role of oxidative stress and inflammation in the left ventricular systolic, diastolic and atrial dysfunction, which are important determinants of the transition of hypertensive heart disease to heart failure with preserved ejection fraction was verified.

The mechanism of reduced longitudinal left ventricular systolic function in hypertensive patients with normal ejection fraction.

Background: MacIver and Townsend's hypothesis predicts, based on a mathematical model of left ventricular contraction, that preserved absolute radial wall thickening (radWT) due to left ventricular hypertrophy is responsible for the normal ejection fraction in patients with heart failure with preserved ejection fraction (HFPEF).

Methods: We tested the validity of this hypothesis by detailed echocardiography including evaluation of ventricular myocardial strain (S) using speckle tracking imaging in at least 60-year-old 18 controls and 94 hypertensive patients with normal ejection fraction.

Results: Echocardiography revealed no left ventricular diastolic dysfunction in 38 out of 94 (40%) patients with hypertension (HTDD-negative group), and 56 out of 94 (60%) patients had diastolic dysfunction (HTDD-positive groups).

Inflammation and oxidative stress caused by nitric oxide synthase uncoupling might lead to left ventricular diastolic and systolic dysfunction in patients with hypertension.

Objective: To investigate the role of oxidative stress, inflammation, hypercoagulability and neuroendocrine activation in the transition of hypertensive heart disease to heart failure with preserved ejection fraction (HFPEF).

Methods: We performed echocardiography for 112 patients (≥ 60 years old) with normal EF (18 controls and 94 with hypertension), and determined protein carbonylation (PC), and tetrahydrobiopterin (BH4), C-reactive protein (CRP), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), fibrinogen, plasminogen activator inhibitor type-I (PAI-I), von Willebrand factor, chromogranin A (cGA) and B-type natriuretic peptide (BNP) levels from their blood samples.

Results: We found that 40% (38/94) of the patients with hypertension (HT) had no diastolic dysfunction (HTDD-), and 60% (56/94) had diastolic dysfunction (HTDD+).

Current algorithms for the diagnosis of wide QRS complex tachycardias.

The differential diagnosis of a regular, monomorphic wide QRS complex tachycardia (WCT) mechanism represents a great diagnostic dilemma commonly encountered by the practicing physician, which has important implications for acute arrhythmia management, further work-up, prognosis and chronic management as well. This comprehensive review discusses the causes and differential diagnosis of WCT, and since the ECG remains the cornerstone of WCT differential diagnosis, focuses on the application and diagnostic value of different ECG criteria and algorithms in this setting and also provides a practical clinical approach to patients with WCTs.