A Reappraisal of the Mitral B-Bump (B-Inflection): Its Relationship to Left Ventricular Dysfunction

A prolonged AC interval, decreased PR - AC interval, and a B-inflection ("bump" or "notch") on the mitral AC slope, have been widely regarded as evidence of abnormally high LVEDP for the last 16 years. However, several groups have questioned the reliability of these signs as predictors of high LVEDP. In 50 patients subjected to LV catheterization, we found no correlation between LVEDP and the AC interval or PR - AC interval. A better correlation was obtained between the presence of a B-inflection and diminished LV ejection fraction on angiocardiography. In our series, the B-inflection was noted in 1/19 patients with LVEDP < 15 mmHg as well as LV ejection fraction > 55%, but it was present in 7/10 patients with LVEDP over 15 mmHg, as well as LV ejection fraction < 55%. When properly recorded, the presence of a B-inflection is a useful sign of significant LV dysfunction.     

New Method for Imaging Innervation of the Renal Preglomerular Vasculature. Alterations in Hypertensive Rats

Objective : To develop a new method for viewing adrenergic innervation along renal preglomerular vessels; to assess nerve densities and vascular lesions along arcuate arteries (ArcA), arcuate arterial branches (ArcB), and interlobular arteries (ILA) in spontaneously hypertensive rats (SHR) and in angiotensin II (AngII) and in N^G‐nitro‐l ‐arginine methyl ester (l ‐NAME) hypertensive rats. Methods : Preglomerular vasculatures were isolated after HCl maceration and were immunostained against synaptophysin, a membrane protein of synaptic vesicles. Lesions were stained with Sudan black. Longitudinal nerve densities and relative frequencies of ArcA, ArcB, and ILA endowed with sudanophilic lesions were assessed separately. Results : Synaptophysin immunostaining revealed the vascular neural plexus. Nerves were adrenergic, as the plexus was destroyed by treatment with 6‐hydroxy dopamine. Vascular lesions were not seen in SHR, and increased nerve density was observed along ArcA and ILA. In l ‐NAME‐ and AngII‐hypertensive rats, vascular lesions affected predominantly ArcB and ILA, and nerve density was reduced by 12% and 28% (ArcA), 37% and 31% (ArcB), and by 55% and 34% (ILA), respectively, versus normotensive controls. Endothelin‐1 receptor blockade did not affect AngII‐induced hypertension but prevented both lesion development and reduction of density of the vascular neural plexus. Conclusions : The method we have devised provides a direct en face view of the vascular adrenergic innervation of isolated preglomerular vasculature. Measurements in hypertensive rat models suggest a link between vascular lesions and reduction in nerve density in hypertension. Endothelin‐1 likely plays a key role in mediating both vascular injury and altered vascular nerve density in hypertension.     

Non-invasive diagnosis of a pericardial cyst. Combined use of M-mode echocardiography and computed tomography

The case of a left-sided pericardial cyst (PC) in a 24 yearold asymptomatic patient is presented. Review of previous chestX-rays indicated that the PC had developed within five years.The PC could be clearly identified by M-mode echocardiography(E); the pattern, however, was similar to that of a pseudoaneurysmof the left ventricle, the latter being an important differentialdiagnosis. Computed tomography (CT) showed not only the positionand size of the PC but allowed, based on attenuation values,a clear differentiation between a pseudoaneurysm and a cysticstructure filled with an aqueous solution. The combined useof E and CT seems to represent a valuable non-invasive toolin the diagnosis of abnormal configurations of the left ventricle.     

Post‐cholecystectomy cystic duct stump leak: a preventable morbidity

OBJECTIVE:  While major bile duct injury is the most serious complication following laparoscopic cholecystectomy, bile leak from the cystic duct stump remains the commonest morbidity. This is a retrospective assessment of all patients who had a cholecystectomy over a 5‐year period from April 2003 to March 2008. METHODS:  Data related to bile leakage were obtained from the Unisoft endoscopic retrograde cholangio‐pancreatography (ERCP) database. RESULTS:  Overall 2011 cholecystectomies were performed, of which 488 were done as emergency procedures. Thirteen patients had significant bile leakage, three of which were from accessory ducts, in one the source could not be identified and nine had a cystic duct stump leak (CDSL), which formed the basis of this study. Eight of the nine CDSL patients had successful ERCP and stenting. One had a percutaneous trans‐hepatic cholangiography and stenting. CDSL following emergency laparoscopic cholecystectomy was up to threefold higher than after elective procedures. CONCLUSION:  The CDSL of 0.44% was comparable to the reported incidence in the literature. Endoscopic management remains the treatment of choice. Emergency cholecystectomies seem to have a higher incidence of CDSL.     

Identifying Opportunities to Strengthen the Public Health Informatics Infrastructure: Exploring Hospitals’ Challenges with Data Exchange

Policy Points

• Even though most hospitals have the technological ability to exchange data with public health agencies, the majority continue to experience challenges.
• Most challenges are attributable to the general resources of public health agencies, although workforce limitations, technology issues such as a lack of data standards, and policy uncertainty around reporting requirements also remain prominent issues.
• Ongoing funding to support the adoption of technology and strengthen the development of the health informatics workforce, combined with revising the promotion of the interoperability scoring approach, will likely help improve the exchange of electronic data between hospitals and public health agencies.

ContextThe novel coronavirus 2019 (COVID‐19) pandemic has highlighted significant barriers in the exchange of essential information between hospitals and local public health agencies. Thus it remains important to clarify the specific issues that hospitals may face in reporting to public health agencies to inform focused approaches to improve the information exchange for the current pandemic as well as ongoing public health activities and population health management.MethodsThis study uses cross‐sectional data of acute‐care, nonfederal hospitals from the 2017 American Hospital Association Annual Survey and Information Technology supplement. Guided by the technology‐organization‐environment framework, we coded the responses to a question regarding the challenges that hospitals face in submitting data to public health agencies by using content analysis according to the type of challenge (i.e., technology, organization, or environment), responsible entity (i.e., hospital, public health agency, vendor, multiple), and the specific issue described. We used multivariable logistic and multinomial regression to identify characteristics of hospitals associated with experiencing the types of challenges.FindingsOur findings show that of the 2,794 hospitals in our analysis, 1,696 (61%) reported experiencing at least one challenge in reporting health data to a public health agency. Organizational issues were the most frequently reported type of challenge, noted by 1,455 hospitals. The most common specific issue, reported by 1,117 hospitals, was the general resources of public health agencies. An advanced EHR system and participation in a health information exchange both decreased the likelihood of not reporting experiencing a challenge and increased the likelihood of reporting an organizational challenge.ConclusionsOur findings inform policy recommendations such as improving data standards, increasing funding for public health agencies to improve their technological capabilities, offering workforce training programs, and increasing clarity of policy specifications and reporting. These approaches can improve the exchange of information between hospitals and public health agencies.     

Protective effect of pentoxifylline plus thalidomide against septic shock in mice

Mortality caused by septic shock in experimental animals is reduced by thalidomide, an inhibitor of tumour necrosis factor alpha. Another drug that could act on the pathophysiological mechanisms of septic shock is pentoxifylline, an inhibitor of platelet aggregation that increases the flexibility of the erythrocyte membrane and has fibrinolytic activity. We studied the effect of pentoxifylline alone and combined with thalidomide in septic shock; 97 NIH mice were injected with lipopolysaccharides of Salmonella abortus equi and D galactosamine. Animals were separated in 4 groups; group A (n = 20) was used as control, group B (n = 15) received thalidomide 50 mg/kg, group C (n = 20) received pentoxifylline 40 mg/kg, and group D (n = 15) received thalidomide plus pentoxifylline. Mortality was recorded every hour. Additionally, 5 animals from each group were sacrificed 8 h after the induction of septic shock for histological analysis of heart, lung, brain, kidney, small intestine, adrenal glands and liver. Microscopic findings were rated as absent, mild, moderate and severe damage. In control animals histological analysis showed intense haemorrhage and necrosis in all organs studied. When compared with controls, treatment with pentoxifylline plus thalidomide reduced mortality (P < 0.03). The tissue damage was less severe in animals from the groups that received pentoxifylline or pentoxifylline plus thalidomide (P < 0.05). Pentoxifylline seems to potentiate the beneficial effects of thalidomide, reducing mortality and attenuating the pathological changes produced by septic shock.     

Stress-Specific Influences of Opioids on Cardiac Electrical Stability

Opioids and Arrhythmias. Evidence is provided indicating that the action of opioids on cardiac electrical stability is contingent on the nature of the stress that impinges on the myocardium. This concept is illustrated by the studies of three clinically relevant conditions, namely, acute behavioral stress, hemorrhage, and myocardial ischemia. During aversive conditioning in dogs, morphine sulfate has been found to prevent the stress-induced reduction in cardiac electrical stability. This protective effect is significantly blunted by administration of atropine, indicating that enhanced vagal activity plays a major role. However, there is a remaining component of morphine's action, which is probably due to reduced perception of the aversive stress. In the context of hemorrhage, the mu-selective agonist fentanyl substantially reduces the profibrillatory effect of this physiological stress. The main mechanism involved in this condition is amplification of baroreceptor sensitivity leading to inhibition of cardiac sympathetic drive. Full activation of mu receptors with fentanyl is also effective in reducing vulnerability to fibrillation during acute coronary artery occlusion. This effect was due to vagal efferent activation and not to enhanced baroreceptor responsiveness as in the case of hemorrhage. Administration of the partial mu-agonist buprenorphine does not exert an antifibrillatory action. Collectively, these results not only demonstrate the potent stabilizing influence of opioids on cardiac rhythm but also the stress specificity of the intermediary mechanisms.     

True Incidence of Pacemaker Syndrome

HELDMAN, D., ET AL.: True Incidence of Pacemaker Syndrome. Although the purported incidence of pacemaker syndrome according to the literature is only 5%–15%, this is based on a series of patients with VVI pacing. Increasing numbers of studies are being reported in which patients prefer the dual chamber mode despite little benefit being demonstrated on objective testing, suggesting that pacemaker syndrome may be more common than is generally reported. This study was designed to evaluate the reported symptoms in a series of patients programmed to both the VVI and one or more dual chamber modes. Forty unselected patients with dual chamber pacemakers were entered into a blind, randomized trial comparing the symptoms associated with VVI pacing to those associated with dual chamber pacing. Patients were randomized to either WI or dual chamber pacing. At the end of 1 week, questionnaires rating 16 different symptoms were completed. Blood pressure, LV function, presence of ventriculoatrial conduction, and ability to override the pacemaker were evaluated. The pacemaker was then programmed to the other mode. Overall, 12 of 16 symptoms were significantly worse in the VVI as compared to dual chamber mode. The most highly significant (p < 0.005) were shortness of breath, dizziness, fatigue, pulsations in the neck or abdomen, cough, and apprehension. Pacemaker syndrome was clinically recognized in 83% of patients paced in the WI mode with 65% of patients experiencing moderate to severe symptoms. There were no readily identified clinical, hemodynamic, or electrophysiological parameters that predicted which patients would develop pacemaker syndrome. Thus, when patients have an opportunity to experience both pacing modes in close proximity to one another, there is a high incidence of pacemaker syndrome in the VVI mode.