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The mechanism of aberrancy of so-called atrioventricular (A-V) Junctional escape beats was investigated in 8 cases, in 5 of which His bundle electrography was performed with both conducted and escape beats recorded. Aberrancy in Junctional beats usually shows features of incomplete or complete right bundle branch block and leftward or rightward shift of the QRS axis in the frontal plane. From the morphologic point of view the aberrancy resembles that seen in conducted beats with the additional feature of bifascicular block. Functional aberrancy based on incomplete recovery of the conduction fibers cannot account for aberrancy in slow Junctional rhythms. Phase 4 depolarization may explain the aberrancy in slow heart rates but cannot readily account for the fusion complexes so frequently seen in these rhythms. His bundle electrography in the present study showed a time relation between His spikes and the onset of the QRS complex which excludes the possibility of antegrade conduction of the aberrant beats along the same pathway used by descending sinus beats as well as true Junctional beats descending through the main His bundle. Specifically, the His spikes were found at or near the onset of the QRS complexes in aberrant escape beats, whereas they were ahead of the QRS complexes by the expected interval of 40 to 50 msec in the conducted beats. This temporal relation favors propagation of escape impulses from their origin bidirectionally, that is, simultaneously toward the ventricular myocardium and retrograde toward the main His bundle. This observation, together with the right bundle branch block and the axis deviation, places the escape focus in 1 of 2 fascicles of the left bundle branch: in the superior division for beats displaying right axis deviation and in the inferior division for beats displaying left axis deviation. With acceptance of a fascicular origin for these beats, a satisfactory explanation becomes readily available for the fusion complexes.

A case of complete left bundle branch block with several episodes of intermittent marked right axis deviation is presented. All possible causes of the intermittent development of additional right axis deviation, such as electrolyte imbalances, lateral wall infarct, intermittent Wolff-Parkinson-White conduction, right bundle branch block, right ventricular hypertrophy and pulmonary embolism, were excluded. We conclude that the explanation for left bundle branch block with intermittent right axis deviation in our patient was the coexistence of left posterior hemiblock and predivisional left bundle branch block.

Implantable transvenous endocardial pacemakers in patients with complete heart block have introduced a host of interesting auscultatory findings into clinical medicine. Some of these, such as variable intensity of first heart sound, were the consequences of the basic conduction abnormality and thus unaffected by pacing, while others, such as “pacemaker heart sounds,” were the result of pacemaker insertion and thus iatrogenic. In either case, physicians who are to take care of an ever-increasing number of patients with intracardiac pacemakers should be familiar with these different auscultatory phenomena.

This paper systematically reviewed national COVID-19 vaccine deployment plans across 20 European countries. Multiple high-quality studies have shown odds ratios for comorbid severe mental illness, and schizophrenia in particular, to equal or even surpass those of other risk comorbidities included for prioritization. Evidence-based policy would then require severe mental illness to be included in the list of risk comorbidities. Yet several sources of bias may have caused the risks associated with severe mental illness to be overlooked by most countries. Mental disorders are often not included as predictors in COVID-19 outcome studies. Studies specifically investigating the risks of psychiatric comorbidity have not yet been summarized in systematic reviews or meta-analyses and were therefore ignored by some national strategies and mathematical models. In summary, European countries' vaccination strategies try to balance ethical and scientific evidence, but for individuals with severe mental illness an evidence policy disconnect remains. Most of these patients are treated in the community, and are currently overlooked by the majority of European COVID-19 vaccination strategies. (PsycInfo Database Record (c) 2021 APA, all rights reserved)