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Introduction Volume depletion can trigger atrial fibrillation through the alteration of the balance of autonomic tone. Hemodynamic response to crystalloid infusion has never been investigated in Paroxysmal AF patients. In this pilot study we have evaluated volume expansion response using Doppler echocardiogaphy in a group of patients coming to our Emergency Department because of symptomatic paroxysmal AF. Methods In a group of consecutive Paroxysmal AF patients we performed a comprehensive echocardiographic examination including Vena Cava diameters and inspiratory collapse rate (from bidimensional subxiphoid view) and including Left Ventricular Outflow time–velocity integral (as mean value of 10 consecutive cardiac cycles). Those with mitral, aortic or tricuspid regrgitation of grade higher than 2+/4+, mitral stenosis, prosthethic mitral valve, FE Results Fluid challenge showed positive response in 7/13 patients. From ROC curve analysis an inspiratory diameter of 9,5 mm or a respiratory collapse of 52% or more both had a 75% sensitivity for volume challenge responsiveness. Conclusion Accounting for small sample size this preliminary work suggests that non invasive bedside parameters easy to evaluate can guide Paroxysmal AF management with crysalloid infusion on top of standard therapy. 1. Preau S et al Crit Care Med 2016; 45: e290–7 2. Bortolotti P et al Ann Intensive Care 2018; 8: 79

To determine the relative value of exercise two-dimensional echocardiography and 99m Tc methoxyisobutylisonitrile single photon emission computed tomography (MIBI SPECT) for the detection of myocardial ischaemia, 103 consecutive patients with either proven or suspected coronary artery disease, who were referred for perfusion scintigraphy, were studied by a combination of the two techniques during the same symptom-limited upright bicycle exercise test. Appropriate echocardiographic images were recorded both at rest and immediately post-exercise and subsequently analysed by means of digital cine loop processing. Both echocardiographic and MIBI SPECT images were visually analysed. For each technique, three different responses to exercise were defined: normal (absence of rest and exercise abnormalities); ischaemic (transient scintigraphic perfusion defects and transient wall motion abnormalities during exercise echocardiography); and fixed abnormalities (fixed scintigraphic perfusion defects; echocardiographic wall motion abnormalities at rest without worsening after exercise). To allow a valid comparison of each technique in localizing ischaemia, the left ventricle was divided into the following six major regions for both methods: anterior, posterolateral, inferior, interventricular septum (subdivided in anterior and posterior septum) and apex. Eleven of the 103 patients had to be excluded from the final analysis because of unsatisfactory examinations: seven with non-interpretable exercise echocardiograms and four with non-interpretable MIBI SPECT images. The response to exercise was concordantly classified by both techniques in 84% of patients (k = 0.78). Exercise echocardiography revealed the presence of ischaemia in 38 and MIBI SPECT in 45 patients (agreement = 77%).(ABSTRACT TRUNCATED AT 250 WORDS)

We evaluated whether the dobutamine stress-echo test can select responders to cardiac resynchronization therapy (CRT). Up to 50% of patients do not respond to CRT. Lack of response may be due to a significant amount of scar or fibrotic tissue at myocardial level.We studied 42 CRT patients. After clinical and echocardiographic evaluation, all patients underwent a dobutamine stress-echo test to assess contractile reserve. Cut-off for the test was an increase of 25% of the left ventricular ejection fraction. Patients were implanted with a CRT-defibrillator and followed up at 6 months. Cut-off for CRT response was a reduction of 15% of left ventricular end-systolic volume. Twenty-five patients responded to CRT; all of them showed presence of contractile reserve. The test showed a sensitivity of 100% and a specificity of 88%.Contractile reserve was a strong predictive factor of response to CRT in the studied population.

Background Although cardiac resynchronization therapy (CRT) has a well-demonstrated therapeutic effect in selected patients with advanced heart failure on optimized drug therapy, nonresponder rate remains high. The LODO-CRT is designed to improve patient selection for CRT. Design and rationale of this study are presented herein. Methods LODO-CRT is a multicenter prospective study, started in late 2006, that enrolls patients with conventional indications for CRT (symptomatic stable New York Heart Association class III-IV on optimized drug therapy, QRS ≥120 milliseconds, left ventricular [LV] dilatation, LV ejection fraction ≤35%). This study is designed to assess the predictive value of LV contractile reserve (LVCR), determined through dobutamine stress echocardiography (defined as an LV ejection fraction increase >5 units), in predicting CRT response during follow-up. Assessment of CRT effects will follow 2 sequential phases: in phase 1, CRT response end point is defined as LV end-systolic volume reduction ≥10% at 6 months; in phase 2, both LV end-systolic volume reduction and clinical status via a clinical composite score will be evaluated at 12 months follow-up. Predictive value of LVCR will be compared to other measures, such as LV dyssynchrony measures, through adjusted multivariable analysis. For the purpose of the study, target patient number is 270 (with 95% confidence, 80% power, α ≤ .05). Enrollment should be complete by the end of 2008. Conclusions The LODO-CRT trial is testing the hypothesis that LVCR assessment, using low-dose dobutamine stress echocardiography test, should effectively predict positive response to CRT both in terms of the reverse remodeling process as well as favorable long-term clinical outcome. Moreover, the predictive value of LVCR will be compared to that of conventional intra-LV dyssynchrony measures.

Following a Mustard's procedure, transoesophageal echocardiography allowed the visualization of all 4 pulmonary veins in 7/12 patients (mean age 14.8 years) and of three veins in a further 2 patients. Both upper pulmonary veins could be visualized consistently. No patient had an isolated pulmonary venous stenosis. In 9 patients in sinus rhythm, computer analysis of Doppler tracings from the left upper pulmonary vein showed significantly lower systolic peak velocities (mean 0.39 +/- 0.10 m/s) and time velocity integrals (mean 6.9 +/- 1.66 cm) than in normal subjects (mean 0.6 +/- 0.09 m/s and 14.4 +/- 2.97 cm respectively; P less than 0.001). We postulate that this is due to compromised atrial relaxation and compliance. In contrast, patients in junctional rhythm (mean 10.7 vs. 7.7 cm in normal subjects). Flow reversal during early ventricular systole (due to tricuspid regurgitation or atrial contraction after retrograde conduction during junctional rhythm) was detected in 6/12 patients. These results confirm that the transoesophageal approach should allow the identification of isolated pulmonary venous obstruction after a Mustard procedure. In addition. detailed analysis of tracings of flow in the pulmonary veins can document the presence of compromised atrial relaxation and help to evaluate the severity of tricuspid regurgitation. It may provide a new index with which to assess impaired systemic ventricular function.

The history of intravascular ultrasound imaging, recent developments in catheter technology, and the initial in vivo experience are reviewed. Additionally, the article also discusses the potential applications of intravascular ultrasound imaging in coronary and peripheral arterial atherosclerosis, hypertension, pulmonary arterial disorders, valvular heart disease, aortic abnormalities, and in congenital heart disorders. Possible future directions are outlined.

In a prospective study, atrial morphology was evaluated by both transoesophageal and precordial echocardiography in 86 unoperated children with congenital heart disease (age range = 0.2 to 14.8 years, mean = 3.8 years) to determine what advantages, if any, might be inherent in the transoesophageal approach. The information derived from both ultrasound approaches was correlated and compared to information obtained during subsequent cardiac catheterization (78 patients) and, or, surgical inspection (53 patients). Atrial appendage morphology and hence atrial situs was determined by transoesophageal echocardiography in every case (82 solitus, two right atrial isomerism, two left atrial isomerism). In addition, the transoesophageal approach indicated left juxtaposition in four patients, compared to only one by precordial examination. Probe patency of the foramen ovale was correctly predicted in 21 patients by transoesophageal imaging, but in only 10 by precordial imaging. In two children significant secundum defects, undetected by the precordial route, were identified. Multiple atrial septal defects were correctly defined in four patients by transoesophageal study but in only one by precordial study. Sinus venosus defects were documented in four by the transoesophageal approach, but in only one by the precordial. Primum defects were equally well documented (nine patients) by either technique, but the associated valve leaflet morphology was better documented by transoesophageal study in 5/9. A subtotal cor triatriatum was diagnosed in one child only by transoesophageal investigation. Transoesophageal echocardiography allows a much more detailed evaluation of atrial morphology than precordial imaging even in infants. It provides direct diagnosis of atrial situs, detection of juxtaposed atrial appendages and improved demonstration or definitive exclusion of atrial septal defects.

Background— Current recommendations require a QRS duration of ≥120 ms as a condition for prescribing cardiac resynchronization therapy (CRT). This study was designed to test the hypothesis that patients with heart failure (HF) of ischemic origin, current indications for defibrillator implantation, and QRS Methods and Results— Patients with intraventricular dyssynchrony on echocardiography were randomly assigned to CRT or dual-chamber defibrillator implantation (CRT defibrillator and dual-chamber implantable cardioverter-defibrillator arm, respectively). The primary end point was the HF clinical composite response, which scores patients as improved, unchanged, or worsened. The secondary end point was the cumulative survival from HF hospitalization and HF death. An additional secondary end point was the composite of HF hospitalization, HF death, and spontaneous ventricular fibrillation. Twenty-three of 56 patients with CRT defibrillator showed an improvement in their clinical composite response at 1 year, compared with 9 of 55 patients with dual-chamber implantable cardioverter-defibrillator (41% versus 16%; P =0.004). After a median follow-up of 16 months, the CRT defibrillator arm showed a nonsignificant higher survival from HF hospitalization and HF death ( P =0.077), and a significantly higher survival from the combined end point of HF hospitalization, HF death, and spontaneous ventricular fibrillation ( P =0.028). Conclusions— In this comparison of CRT defibrillator and dual-chamber implantable cardioverter-defibrillator, CRT improved clinical status in some patients with ischemic cardiomyopathy, mild-to-moderate symptoms, narrow QRS duration, and mechanical dyssynchrony on echocardiography. Clinical Trial Registration— URL: http://clinicaltrials.gov . Unique identifier: NCT01577446.

To evaluate whether histamine exerts a direct effect on coronary hemodynamics in humans, and to investigate the role played by H1and H2receptors in this response, intracoronary saline solution or histamine (4 μg) was administered in 10 patients with normal coronary arteries during diagnostic cardiac catheterization. Histamine injection was repeated after intravenous Cimetidine (400 mg) and diphenhydramine (10 mg). The electrocardiogram, arterial pressure and thermodilution coronary blood flow were continuously monitored during and for 40 seconds after each injection.Immediately after histamine injection there was a significant increase in coronary blood flow (65 ± 6%) and a decrease in coronary vascular resistance ( − 40 ± 3%) (both p < 0.001), with minor changes in the RR interval and the mean arterial pressure. H2receptor blockade with Cimetidine did not affect these changes, while H1receptor blockade with diphenhydramine sig- nificantly reduced the histamine-induced increase in coronary blood flow and the decrease in coronary vascular resistance (26 ± 6%, p < 0.005 and −18 ± 5%, p < 0.001, respectively). Twenty to 30 seconds after histamine injection, a significant decrease in mean arterial pressure (−17 ± 2%, p < 0.001) and in the RR interval (−4 ± 1%, p < 0.01) was observed. These changes persisted after H2receptor blockade with Cimetidine, but were completely abolished after H1receptor blockade with diphenhydramine. In each case coronary and systemic hemodynamics returned to normal within 40 seconds of the injection.Therefore, in patients with normal coronary arteries, histamine induces a direct dilation of the small resistance coronary arteries, regardless of myocardial metabolic requirement, that is predominantly, but not completely, mediated by H1receptors.