Macrolide resistance in Mycoplasma genitalium in Catalonia, Spain: a 1 year prospective study.

BACKGROUND: Mycoplasma genitalium is an emergent cause of sexually transmitted disease (STD). The first-line treatment is azithromycin, but macrolide resistance is increasing due to mutations in the 23S rRNA gene. OBJECTIVES: To determine the rates of M. genitalium infection and macrolide resistance in an area adjacent to Barcelona. METHODS: This 1 year prospective study was performed in a heterogenous population that included both low- and high-risk patients. M. genitalium was detected in all specimens sent to our institution for STD detection. Epidemiological and relevant clinical data were collected in the positive cases. Characterization of macrolide-associated resistance was performed by 23S rDNA sequencing. RESULTS: Of the 3540 patients included, 132 (3.7%) were positive for M. genitalium. Another sexually transmitted bacteria was detected in 20.4% of the M. genitalium cases, and Chlamydia trachomatis (11%) was the most frequently co-detected microorganism. Only 61.4% of patients received an adequate initial treatment against M. genitalium. The test of cure (TOC) was performed in 42% of patients, and therapeutic failure was detected in 10 cases. The rate of macrolide resistance was 12.6% and the most prevalent mutation was A2058G. There was an association between macrolide resistance and a previous history of M. genitalium detection (P < 0.001). CONCLUSIONS: Our results support the contribution of the previous use of macrolides in resistant strains. Given the difficulties in performing TOC in all patients, the inclusion of macrolide resistance in the detection test should be mandatory.

Multi-source datasets acquired over Toulouse (France) in 2021 for urban microclimate studies during the CAMCATT/AI4GEO field campaign.

The CAMCATT-AI4GEO extensive field experiment took place in Toulouse, a city in the southwest of France, from 14th to 25th June 2021 (with complementary measurements performed on the 6 September 2021). Its main objective was the acquisition of a new reference dataset on an urban site to support the development and validation of data products from the future thermal infrared (TIR) satellite missions such as TRISHNA (CNES/ISRO), LSTM (ESA) and SBG (NASA). With their high spatial (between 30-60m) and temporal (2-3 days) resolutions, the future TIR satellite data will allow a better investigation of the urban climate at the neighbourhood scale. However, in order to validate the future products of these missions such as LST, air temperature, comfort index and Urban Heat Island (UHI), there is a need to accurately characterise the organisation of the city in terms of 3D geometry, spectral optical properties and both land surface temperature and emissivity (LST and LSE) at several scales. In this context, the CAMCATT-AI4GEO field campaign provides a set of airborne VISNIR-SWIR (Visible Near InfraRed - ShortWave InfraRed) hyperspectral imagery, multispectral thermal infrared (TIR) imagery and 3D LiDAR acquisitions, together with a variety of ground data collected, for some of them, simultaneously to the flight. The ground dataset includes surface reflectance measured spectrally with ASD spectroradiometers and in six spectral bands spreading from shortwave to thermal infrared and for two viewing angles with a SOC410-DHR handheld reflectometer. It is completed with LST and LSE retrieved from thermal infrared radiance acquired in six spectral bands with CIMEL radiometers. It also includes meteorological data coming from four radio soundings (one of which was taken during the flight), data routinely collected at the Blagnac airport reference station as well as air temperature and humidity acquired using instrumented cars following two different itineraries. In addition, a link is provided to access the data routinely collected by the network of weather stations set up by Toulouse Metropole in the city and its surroundings. This data paper describes this new reference urban dataset which can be useful for many applications such as calibration/validation of at-surface radiance, LST and LSE data products as well as higher level products such as air temperature or comfort index. It also provides valuable opportunities for other applications in urban climate studies, such as supporting the validation of microclimate models.

Intermediate snowpack melt-out dates guarantee the highest seasonal grasslands greening in the Pyrenees.

In mountain areas, the phenology and productivity of grassland are closely related to snow dynamics. However, the influence that snow melt timing has on grassland growing still needs further attention for a full understanding, particularly at high spatial resolution. Aiming to reduce this knowledge gap, this work exploits 1 m resolution snow depth and Normalized Difference Vegetation Index observations acquired with an Unmanned Aerial Vehicle at a sub-alpine site in the Pyrenees. During two snow seasons (2019-2020 and 2020-2021), 14 NDVI and 17 snow depth distributions were acquired over 48 ha. Despite the snow dynamics being different in the two seasons, the response of grasslands greening to snow melt-out exhibited a very similar pattern in both. The NDVI temporal evolution in areas with distinct melt-out dates reveals that sectors where the melt-out date occurs in late April or early May (optimum melt-out) reach the maximum vegetation productivity. Zones with an earlier or a later melt-out rarely reach peak NDVI values. The results obtained in this study area, suggest that knowledge about snow depth distribution is not needed to understand NDVI grassland dynamics. The analysis did not reveal a clear link between the spatial variability in snow duration and the diversity and richness of grassland communities within the study area.

Improving multi-technique monitoring using Sentinel-1 and Cosmo-SkyMed data and upgrading groundwater model capabilities.

Aquifer-systems have become a strategic source of fresh water in the present climatic conditions, especially under stress in arid regions like the Iberian Mediterranean Arc. Understanding the behavior of groundwater reservoirs is crucial to their well-management and mitigation of adverse consequences of overexploitation. In this work, we use space geodetic measurements from satellite interferometric synthetic aperture radar (InSAR) and Global Positioning System (GPS) data, covering the period 2011-2017, to predict and validate the ground surface displacement over the fastest subsiding basin due to groundwater withdrawal in Europe (>10 cm/year). The 2D decomposition of InSAR displacements from Cosmo-SkyMed and Sentinel-1 satellites allows us to detect horizontal deformation towards the basin center, with a maximum displacement of 1.5 cm/year. InSAR results were introduced in a newly developed methodology for aquifer system management to estimate unknown pumping rates for the 2012-2017 period. This study illustrates how the combination of InSAR data, groundwater flow and deformation models can be used to improve the aquifer-systems sustainable management.

RECALMIN. Four years of growth of the internal medicine units of the Spanish National Health System (2013-2016). / RECALMIN. Cuatro años de evolución de las Unidades de Medicina Interna del Sistema Nacional de Salud (2013-2016).

OBJECTIVES: To compare the structure, resources and activity of the internal medicine units (IMUs) of the Spanish National Health System (SNHS) in 2013 and 2016. To analyse the differences between IMUs in 2016 by hospital size. MATERIAL AND METHODS: We conducted a comparison of 2 descriptive cross-sectional studies of IMUs in general acute care hospitals of the Spanish National Health System, with data referring to 2013 and 2016. The variables were collected via an ad hoc questionnaire (RECALMIN survey). RESULTS: Between 2013 and 2016, the demand for care increased dramatically (with an annual average of 11% in hospital discharges and 16% in first consultations), and comorbidity slightly increased (2%). During this period, the mean productivity of IMUs increased 16.7% (0.6±0.3 vs. 0.7±0.3; P=.09), and the mean stay decreased 10% (9±2.2 vs. 8.1±2.1 days; P=.001). Progress in implementing good practices and systematic care for complex chronic patients was scarce. Both surveys found variability among IMUs and marked differences among IMUs of hospitals of different sizes. CONCLUSIONS: IMUs responded to the increased burden of care they supported during 2013-2016 by improving their efficiency and productivity; however, advances in implementing good practices, including care for chronic complex patients, were scare. The significant variability in the indicators of structure, activity and management models found in 2013 remained in 2016.

RECALMIN II. Eight years of hospitalisation in Internal Medicine Units (2007-2014). What has changed? / RECALMIN II. Ocho años de hospitalización en las Unidades de Medicina Interna (2007-2014). ¿Qué ha cambiado?

OBJECTIVES: To analyse the evolution of care provided by the internal medicine units (IMU) of the Spanish National Health System from 2007 to 2014. MATERIAL AND METHODS: We analysed all discharges from the IMU of the Spanish National Health System in 2007 and 2014, using the Minimum Basic Data Set. We compared the risk factors by episode, mortality and readmissions between the two periods. We prepared specific fits for the risk for mortality and readmissions in heart failure, pneumonia and chronic obstructive pulmonary disease, as well as the Charlson index for all activity. RESULTS: Discharges from the IMU between the two periods increased 14%. The average patient age increased by 2.8 years (71.2±17.1 vs. 74±16.2; p<.001), with a marked increase in comorbidity (Charlson index, 4±3.7 vs. 4.7±3.9; p<.001; 24% increase in risk factors per episode). The adjusted mortality rates decreased slight but significantly, with a slight increase in readmissions. CONCLUSIONS: During the analysed period, there was an increase of almost 3 years in the mean age of patients treated in the IMU of the Spanish National Health System, with a marked increase in comorbidity. These results should lead to a more appropriate assignment of nurse workloads and an increased implementation of good practices in clinical management.

Combination therapy with sildenafil and bosentan reverts severe pulmonary hypertension and allows heart transplantation: case report.

INTRODUCTION: Severe pulmonary hypertension with no response to vasodilators on an acute hemodynamic study is a contraindication to cardiac transplantation. The development of oral pulmonary vasodilators improves the prognosis in these patients. We present the case of a patient whose admission to the waiting list for cardiac transplantation was possible after 6 months of combination therapy with Sildenafil and Bosentan. CASE REPORT: The patient was a 50-year-old man with severe dilated alcohol-induced cardiomyopathy. A pretransplantation study, including a right hemodynamic analysis, revealed irreversible pulmonary hypertension, with 59 mm Hg mean pulmonary artery pressure and 6.4 Wood IU pulmonary vascular resistance, with no response to acute vasodilators with nitric oxide or prostacyclin. Initially, heart transplantation was not possible and the patient started treatment with oral Sildenafil. After 6 months there was no improvement in echocardiographic or hemodynamic parameters, and combination therapy with Bosentan was started. With the combination therapy, the patient progressively improved clinically and hemodynamically, the pressures becoming normal at the sixth month, at which time he was included on the waiting list for a heart transplantation. Eight months later he received a graft with a good posttransplantation course, no right ventricular failure in the acute phase, and absence of pulmonary hypertension on echocardiogrphic and invasive studies. CONCLUSION: Combinations of an oral pulmonary vasodilator with diverse action mechanisms may represent an alternative for patients with irreversible pulmonary hypertension who do not respond to monotherapy.

Sirolimus experience in heart transplantation.

INTRODUCTION: Sirolimus is a potent, nonnephrotoxic immunosuppressant with antiproliferative activity in nonimmune cells. Recent data support the conversion in late renal failure secondary to calcineurin inhibitors (CNIs), with limited experience in de novo regimens in patients with predictive factors of postoperative renal impairment. OBJECTIVE: We evaluated our experience of sirolimus-based immunosuppression administered to 25 heart transplant recipients. METHODS: A retrospective analysis of 25 heart transplant recipients who received sirolimus included 17 conversions due to late CNI-related chronic renal dysfunction, six patients with a de novo regimen, and two patients who developed posttransplant pulmonary neoplasms. The conversion from CNI to sirolimus was started with 2 mg, with an average time after transplantation of 78 +/- 43 months and a mean baseline serum creatinine level of 2.1 +/- 0.45 mg/dL. The mean clinical follow-up was 17 +/- 9 months postconversion, and included echocardiography and laboratory studies. In the de novo group successive endomyocardial biopsies were performed during the first semester. RESULTS: Serum creatinine fell from 2.1 +/- 0.45 mg/dL to 1.8 +/- 0.51 mg/dL (P = .012). Mean sirolimus levels were 15 +/- 9 ng/mL (doses 2.2 +/- 0.4 mg). This improvement continued until 3 months (creatinine 1.5 +/- 0.35 P < .01)/sirolimus levels 11.7 +/- 5 ng/mL [1.9 +/- 0.7 mg]), with maintenance at 6 months (1.58 +/- 0.3 mg/dL/14 +/- 4 ng/mL [1.85 +/- 0.7 mg]) and 1-year postconversion (1.53 +/- 0.39 mg/dL; P = .019/10.7 +/- 2.5 ng/mL [1.5 +/- 0.7 mg]). De novo, after a mean follow-up of 13 months (range 3 to 35), sirolimus appeared to increase the incidence of a moderate histological grade of rejection without hemodynamic compromise. Side effects were common (63%), including peripheral edema, skin eruptions, and pericardial effusion. Only one patient discontinued treatment, due to intestinal intolerance. Four patients died during follow-up: two because of lung neoplasms and two because of progressive graft vessel disease. CONCLUSION: Sirolimus improved late CNI-related chronic renal dysfunction. Kidney function was preserved using a de novo CNI-free immunosuppressive regimen for recent cardiac transplant recipients.

Transient entrainment of bundle-branch reentry by atrial and ventricular stimulation: elucidation of the tachycardia mechanism through analysis of the surface ECG.

BACKGROUND: Different responses to entrainment have been reported in relation to the pacing site of a variety of tachycardias. However, transient entrainment of bundle-branch reentrant tachycardia (BBRT) has not been investigated systematically. METHODS AND RESULTS: We attempted entrainment of 13 BBRTs in 9 patients by pacing first the right ventricle and then the right atrium. The initial pacing cycle length (CL) was 10 ms faster than the tachycardia CL. Subsequent pacing sequences were performed with 5- to 10-ms CL decrements until tachycardia termination or loss of postatropine 1:1 AV conduction. Both full ventricular-paced and AV-conducted QRS complex references were obtained during sinus rhythm pacing from the same sites and with similar CL as during entrainment. Transient entrainment was achieved by ventricular and atrial stimulation in 11 and 8 tachycardias, respectively. Constant fusion was always present during entrainment by ventricular stimulation. There was no change in the QRS complex (orthodromically concealed fusion) during entrainment by atrial stimulation in 6 of 6 tachycardias with left bundle-branch block morphology and in 1 of 2 tachycardias with right bundle-branch block morphology. CONCLUSIONS: BBRT, especially if it has a left bundle-branch block morphology, can be differentiated from other wide-QRS-complex tachycardia mechanisms through analysis of the ECGs recorded during tachycardia entrainment by atrial and ventricular stimulation. This diagnostic approach may be especially useful when it is difficult to record a stable or sufficiently sized His bundle electrogram or when spontaneous changes in the ventricular CL precede similar changes in the His bundle CL.

Bundle-branch reentry and the postpacing interval after entrainment by right ventricular apex stimulation: a new approach to elucidate the mechanism of wide-QRS-complex tachycardia with atrioventricular dissociation.

BACKGROUND: Diagnosis of bundle-branch reentry ventricular tachycardia (BBR-VT) by the standard approach is challenging, and this may lead to nonrecognition of this tachycardia mechanism. Because the postpacing interval (PPI) after entrainment has been correlated with the distance from the pacing site to the reentrant circuit, BBR-VT entrainment by pacing from the right ventricular apex (RVA) should result in a PPI similar to the tachycardia cycle length (TCL). This factor may differentiate BBR-VT from other mechanisms of wide-QRS-complex tachycardia with AV dissociation, such as myocardial reentrant VT (MR-VT) or AV nodal reentrant tachycardia (AVNRT), in which the circuit is usually located away from the RVA. METHODS AND RESULTS: Transient entrainment by RVA pacing was attempted in 18 consecutive BBR-VTs and finally achieved in 13. Results were compared with those found in 59 consecutive MR-VTs and 50 consecutive AVNRTs. The mean PPI-TCL difference was significantly (P:<0.0001) shorter in the BBR-VT group (9+/-11 ms) than in the MR-VT (109+/-48 ms) and the AVNRT (150+/-29 ms) groups. No BBR-VT showed a PPI-TCL >30 ms (range -12 to 24 ms). Except for 2 MR-VTs, no MR-VT (range 21 to 211 ms) or AVNRT (range 100 to 215 ms) showed a PPI-TCL <30 ms. CONCLUSIONS: A PPI-TCL >30 ms, after entrainment by RVA stimulation, makes BBR-VT unlikely. Conversely, a PPI-TCL <30 ms is suggestive of BBR-VT but should lead to further investigation by use of conventional criteria.

Control of hypertension in patients at high risk of cardiovascular disease.

BACKGROUND: Hypertension is a major cardiovascular risk factor, but knowledge about the real magnitude of the problem and its determinants is lacking. AIM: To assess control of hypertension and evaluate medical resource use, in patients at high risk of cardiovascular disease. DESIGN: Multicentric cross-sectional study. METHODS: We collected data for 2205 adult patients from 36 centres, representative of all regions of Spain. Patients had attended out-patient clinics from July 2002 to August 2003, had an absolute cardiovascular risk > or =20% at 10 years (according to the Framingham guidelines), and had a diagnosis of hypertension. Pregnant and terminally ill patients were excluded. RESULTS: Hypertension was inadequately controlled in 1384 patients (62.8%). LDL cholesterol was higher in patients with uncontrolled hypertension (median 130.2 vs. 120.0 mg/dl, p < 0.001). Haemoglobin A(1c) in diabetic patients was also greater in those with uncontrolled hypertension (median 7.10% vs. 6.90%, p = 0.010). Uncontrolled hypertension was associated with the following variables, in descending strength of association: higher LDL cholesterol, taking antihypertensive medication, living in non-metropolitan areas, and higher body mass index. DISCUSSION: Hypertension is poorly controlled in most patients with a high risk of cardiovascular disease. Uncontrolled hypertension is frequently associated with poor control of other risk factors.

Prevalence of masked uncontrolled hypertension according to the number of office blood pressure measurements.

INTRODUCTION AND OBJECTIVES: The reported prevalence of masked uncontrolled hypertension (MUCH) varies because many studies are not comparable as they use different measurement methodologies. To evaluate the influence of the number of office blood pressure readings on the prevalence of MUCH we conducted a cross-sectional, multicenter study in treated hypertensive patients. PATIENTS AND METHODS: We carried out an observational, cross-sectional, multicenter study in 33 Spanish hospital-based hypertension units, involving 35 investigators and 12 Autonomous Communities. Six blood pressure readings and a 24-h ambulatory blood pressure monitoring were performed in treated hypertensive patients. The means of the first 3 readings (P123), the 2nd, 3rd and 4th readings (P234), the 3rd, 4th and 5th readings (P345) and the last 3 readings (P456) were compared with mean 24-h blood pressure. MUCH was defined as office blood pressure <140/90mmHg and 24-h blood pressure ≥130/80mmHg, considering the first 3 readings (MUCH123), the 2nd, 3rd and 4th readings (MUCH234), the 3rd, 4th and 5th readings (MUCH345) and the last 3 readings (MUCH456). RESULTS: We included 498 hypertensive patients. Mean (standard deviation) office blood pressure measurements were: (P123) 141(18)/82(11); (P234) 139(17)/81(11); (P345) 138(17)/81(11) and (P456) 137(16)/80(10) mmHg. Mean 24-h blood pressure was 127(13.8)/75(9.5) mmHg. The correlation coefficients between ambulatory and office systolic/diastolic blood pressure were (P123):0.48/0.50; (P234):0.50/0.52; (P345):0.50/0.54; and (P456):0.50/0.55 (p<0.001, all). The prevalences of MUCH123, MUCH234, MUCH345 and MUCH456 were 14.5%, 18.9%, 19.5% and 21.1%, respectively. CONCLUSIONS: The prevalence of MUCH diagnosis depends on the serial office blood pressure readings, being much higher for the last three blood pressure readings. Discarding the first and second office blood pressure measures seems to be the most accurate method for diagnosing MUCH.

Evidence for a visceral afferent origin of substance P-like immunoreactivity in lamina V of the rat thoracic spinal cord.

A visceral afferent origin of substance P-like immunoreactivity in lamina V of the lower thoracic spinal cord of the rat was investigated. In transverse sections from normal animals there was a moderately dense substance P-immunoreactive innervation of lamina V. In some sections there was a dorsoventrally orientated fibre bundle from the superficial dorsal horn entering lamina V. In parasagittal sections, substance P-immunoreactivity in lamina V was found arranged in clusters, with a periodicity in the rostrocaudal axis of 200-600 microns. In some cases these were seen to be continuous with a dorsoventrally orientated fibre bundle from the superficial dorsal horn. After section of the splanchnic nerve there was a consistent reduction in the density of the substance P-like immunoreactivity in lamina V, with fewer clusters on the operated side. Adult rats treated neonatally with capsaicin showed a substantial reduction of substance P-immunoreactivity in laminae I and II and the virtual abolition of staining in lamina V. These results provide evidence of a visceral origin for some of the substance P-like immunoreactivity in lamina V of the rat thoracic spinal cord. In addition, they confirm that most of the substance P-immunoreactivity in the dorsal horn is of primary afferent origin.

Visceral and somatic afferent origin of calcitonin gene-related peptide immunoreactivity in the lower thoracic spinal cord of the rat.

The origin of calcitonin gene-related peptide in the thoracic spinal cord of the rat was investigated by radioimmunoassay and immunohistochemistry. In transverse sections from normal animals there was a dense staining of calcitonin gene-related peptide-immunoreactivity in laminae I, II and V of the dorsal horn. In parasagittal sections this was found to consist of rostrocaudally orientated fibres in laminae I and II and longitudinal bundles of fibres interspersed with a plexus of immunoreactivity in lamina V. After sectioning the thoracic spinal nerves there was a significant reduction in immunoreactivity in the dorsal horn of the spinal cord which was seen as a marked reduction of staining in lamina II and in the bundles of fibres in lamina V. Section of the splanchnic nerve slightly reduced staining in lamina I and virtually abolished the plexuses of immunoreactivity in lamina V. However, measurement of calcitonin gene-related peptide in samples from coeliac-ganglionized rats revealed an increase in immunoreactivity in regions of the spinal cord containing lamina V. These results provide evidence of a visceral and somatic afferent origin of calcitonin gene-related peptide in the thoracic spinal cord of the rat.

Vectorcardiograms in severe aortic insufficiency. Clockwise rotation of QRS loop in the horizontal plane.

In La Paz Hospital, Madrid, recently, vectorcardiograms (VCGs) were performed on 74 patients with aortic insufficiency. These cases presenting electrocardiographic and radiologic signs of left ventricular hypertrophy, were divided into three groups. In 25 patients (Group 1) the QRS loop in the horizontal plane (HP) showed counterclockwise rotation; 43 patients (Group 2) showed clockwise rotation; and 6 patients (Group 3) showed a pattern of left bundle branch block (LBBB). In Group 2, 31 of the 43 patients (group 2-A) had a Qloop of normal orientation and generally increased voltage, and in the remaining 12 patients (group 2-B) the Q loop was absent. All of the patients in Group 2 had severe aortic insufficiency. Thus, that group's valuation of the left ventricular hypertrophy using maximum QRS vector voltage in the HP, was higher than in Group 1 mean 3.75mV in Group 2 versus mean 2.71mV in Group 1 (p less than 0.01). Postoperative VCGs were performed in 12 patients of group 2-A, showing in all of them a clockwise to counterclockwise rotation change of the QRS loop in the HP. On the other hand, this fact was observed in only two of the eight patients in group 2-B. The clockwise rotation of the QRS loop in the HP is an important datum in our report, particularly in the diagnosis of severe aortic insufficiency. Conversely, a clockwise to counterclockwise rotation change would be a positive sign of good post operative evolution. Finally, two reasons are given to explain this anomalous rotation in the horizontal plane: dilatation and fibrosis.

Fascicular block within the His bundle.

The findings in a patient with complete atrioventricular block and normal morphology and duration of the QRS complex are presented. A His bundle electrogram was obtained, which led to the location of the atrioventricular block within the His bundle. A careful review of the electrocardiograms obtained during the seven years preceding the onset of complete atrioventricular block showed a QRS complex with the features of left anterior hemiblock and a progressive impairment of atrioventricular conduction. From these data, we inferred that the different degrees of atrioventricular block and the left anterior hemiblock were caused by lesions within the His bundle involving the fibers destined for the left anterior division of the left branch. After the onset of complete atrioventricular block, with the subsidiary pacemaker located in the His bundle distal to the lesions, the QRS complex became normal, indicating the integrity of the bundle branches and fasciculi. The atrial and proximal His potential intervals and those between distal His and ventricular potentials were normal.

Successful treatment of prosthetic aortic valve mucormycosis.

Mucor endocarditis after cardiovascular surgery is rare and usually fatal. We report the first known case of prosthetic aortic valve mucormycosis in a patient without predisposing risk factors who was successfully treated using a combination of early antifungal drug therapy and surgical removal of infected material.

Vectocardiography in tetralogy of Fallot before and after operation (palliative and corrective surgery).

Vectorcardiograms from 55 patients with diagnosed tetralogy of Fallot were studied and divided into the following three groups: A, 35 nonoperated cases; B, 23 with systemic-pulmonary shunt (nine studied preoperatively and also in A); and C, ten after total correction. In group A, two different types of QRS loop occurred in the horizontal plane (HP); 23 clinically and hemodynamically severe cases had right anterior position with clockwise (C) rotation, and 12 less severe cases had right posterior position with counterclockwise (CC) rotation or figure-8 morphology. In the frontal plane the QRS loop was located inferiorly and to the right, with C rotation (80 percent); two cases had the left anterior hemiblock (LAHB) pattern, and another two severe cases had CC rotation and right superior position. Group B had an evident increase of left ventricular forces in the HP, compared with group A; group-B rotation was preferentially CC or figure-8 morphology. Group C had a pattern of right bundle-branch block in nine cases (classic in one and uncharacteristic in eight); four cases also had LAHB.

Anterograde and retrograde bradycardiac block in the His-Purkinje system. Finding in a patient with acute myocardial infarction.

A patient with an acute inferior myocardial infarction developed a complete atrioventricular block and intermitent periods of atrioventricular conduction with QRS complexes showing right bundle branch block associated with left anterior hemiblock. Recordings of the His bundle electrogram showed that the atrioventricular block was infrahisian and that in periods of resumed atrioventricular conduction, the His-ventricle (H-V) interval was long. Ventricular escape beats showed concealed conduction to the atrioventricular node. Anterograde atrioventricular conduction was always resumed through the left posterior division when the preceding division when the preceding intervals between ventricular escape beats and the atrium (V-A intervals) were shorter than 580 msec. The same phenomenon occurred with right ventricular pacing. A retrograde His potential could be observed. Retrograde conduction of ventricular escape beats and ventricular paced beats was blocked if the H-V interval and the interval between the His bundle and the ventricular paced beat (H-V interval) were long (more than 600 msec and 550 msec, respectively). The existence of an intermittent anterograde and retrograde bradycardiac infrahisian block was inferred from the previously mentioned data; a fixed retrograde atrial nodal block was also present.

Atrioventricular nodal dysfunction in patients with atrial septal defect. Abnormalities of conduction and reciprocal rhythms.

Electrophysiologic studies were performed in 17 unselected patients (mean age, 20 years) with atrial septal defect (ASD) of the ostium secundum type. In nine (52.9 percent) signs were found of atrioventricular (A-V) nodal dysfunction, in seven (41.1 percent) prolonged A-H interval, and in three (17.6 percent) prolonged effective refractory period of A-V node and in five (29.4 percent) A-V nodal tachycardia and reentry. Three of the four cases showed anterograde conduction (Ae-H interval) faster than retrograde conduction (H-A3 interval) during the tachycardia. In one patient with reentry a similar phenomenon was observed. In the remaining patient the conduction time was reversed (Ae-H longer than H-Ae). In two patients infrahisian and intrahisian block (first and second degree) with persistence of the tachycardia was observed. Patent or latent abnormalities in A-V node function are a frequent finding in patients with ASD. In the sinus node, any kind of significant abnormality can be found.