Maltohexaose-indocyanine green (MH-ICG) for near infrared imaging of endocarditis

Infectious endocarditis is a life-threatening disease, and diagnostics are urgently needed to accurately diagnose this disease especially in the case of prosthetic valve endocarditis. We show here that maltohexaose conjugated to indocyanine green (MH-ICG) can detect Staphylococcus aureus (S. aureus) infection in a rat model of infective endocarditis. The affinity of MH-ICG to S. aureus was determined and had a Km and Vmax of 5.4 μM and 3.0 X 10⁻⁶ μmol/minutes/10⁸ CFU, respectively. MH-ICG had no detectable toxicity to mammalian cells at concentrations as high as 100 μM. The in vivo efficiency of MH-ICG in rats was evaluated using a right heart endocarditis model, and the accumulation of MH-ICG in the bacterial vegetations was 2.5 ± 0.2 times higher than that in the control left ventricular wall. The biological half-life of MH-ICG in healthy rats was 14.0 ± 1.3 minutes, and approximately 50% of injected MH-ICG was excreted into the feces after 24 hours. These data demonstrate that MH-ICG was internalized by bacteria with high specificity and that MH-ICG specifically accumulated in bacterial vegetations in a rat model of endocarditis. These results demonstrate the potential efficacy of this agent in the detection of infective endocarditis.

Claviform aspergillus-related vegetation in the left ventricle of a patient with systemic lupus erythematosus

A 38-year-old woman was diagnosed with systemic lupus erythematosus and received immunosuppressive therapy. After 6 months of treatment, workup for low-grade fever yielded elevated enzyme-linked immunosorbent assay titers for Aspergillus antigen in serum and ascites, leading to the diagnosis of disseminated aspergillosis. Transthoracic echocardiography revealed a claviform vegetation attached to the left ventricular anterior septum. Two days after the start of antifungal Amphotericin-B therapy, the patient suffered from several neurologic disorders. A second transthoracic echocardiography revealed that the vegetation decreased in size. Two weeks later, the vegetation increased again. Combination therapy of Amphotericin-B and Voriconazole was initiated, and the vegetation eventually disappeared completely. © 2017 Wiley Periodicals, Inc. J Clin Ultrasound 46:231-232, 2018.

Association between chronic hepatitis C virus infection and high levels of circulating N-terminal pro-brain natriuretic peptide

The association between HCV infection and myocardial disorders remains unclear. This study aimed to assess whether or not HCV infection influences myocardial dysfunction by the use of NT-proBNP, a sensitive marker of myocardial dysfunction. A total of 198 participants [99 patients with chronic HCV infection (aged 46-68 years) and 99 anti-HCV-negative sex and age matched controls] were examined. Serum HCV-RNA level and HCV genotype were tested and liver biopsy was done only for the patient group. The NT-proBNP concentration of the HCV patients (mean 71.6 ± 79.1 pg/ml; median 46.0 pg/ml, range 5.0-400.0) was significantly higher than that of the controls (mean 39.8 ± 24.4 pg/ml; median 35.8 pg/ml, range 7.0-108.0) (P < 0.05). 20.0 % of the HCV patients and 0.6 % of the controls had high NT-proBNP (higher than 125 pg/ml; the single cut off point for patients under 75 years of age) (P < 0.05). Stepwise multiple regression analysis revealed that chronic HCV infection was independently correlated with NT-proBNP level after adjustment for parameters that might influence NT-proBNP (P = 0.005). Our data suggest that chronic HCV infection is associated with increased NT-proBNP, indicating that chronic HCV infection might induce myocardial dysfunction.

Left ventricular mechanical dyssynchrony is load independent at rest and during endotoxaemia in a porcine model

AIM

In diseased or injured states, the left ventricle displays higher degrees of mechanical dyssynchrony. We aimed at assessing mechanical dyssynchrony ranges in health related to variation in load as well as during acute endotoxin-induced ventricular injury.

METHODS

In 16 juvenile anaesthetized pigs, a five-segment conductance catheter was placed in the left ventricle as well as a balloon-tipped catheter in the inferior vena cava. Mechanical dyssynchrony during systole, including dyssynchrony time in per cent during systole and internal flow fraction during systole, were measured at rest and during controlled pre-load reduction sequences, as well as during 3 h of endotoxin infusion (0.25 microg kg(-)1 h(-1)).

RESULTS

Systolic dyssynchrony and internal flow fraction did not change during the course of acute beat-to-beat pre-load alteration. Endotoxin-produced acute pulmonary hypertension by left ventricular dyssynchrony measures was not changed during the early peak of pulmonary hypertension. Endotoxin ventricular injury led to progressive increases in systolic mechanical segmental dyssynchrony (7.9 +/- 1.2-13.0 +/- 1.3%) and ventricular systolic internal flow fraction (7.1 +/- 2.4-16.6 +/- 2.8%), respectively for baseline and then at hour 3. There was no localization of dyssynchrony changes to segment or region in the ventricular long axis during endotoxin infusion.

CONCLUSION

These results suggest that systolic mechanical dyssynchrony measures may be load independent in health and during acute global ventricular injury by endotoxin. More study is needed to validate ranges in health and disease for parameters of mechanical dyssynchrony.

Fatal myocarditis related to Campylobacter jejuni infection: a case report

Infectious myocarditis can be caused by a variety of agents, with enteroviruses being the most common. Myocarditis due to enteric bacteria is rare. We present pathological documentation of a rare case of a Campylobacter jejuni bowel infection leading to rapidly fatal myocarditis.

Biventricular mural vegetations in a patient without valvular pathology

We present the case of a 40 year-old man with biventricular nonvalvular vegetations presenting with acute onset of unilateral hearing loss and headache as a result of septic emboli. The medical literature involving the rare diagnosis of mural vegetation is reviewed and unusual features of this case are discussed.

Fatal endocarditis in Wegener's granulomatosis: mitral valve involvement and an intracardiac mass

Reported here is a 39-year-old man with Wegener's granulomatosis who had died due to endocarditis during his follow up. The concomitance of these two pathologies is discussed in the light of the pertinent literature.

Prosthetic valve endocarditis caused by Scedosporium apiospermum

Scedosporium apiospermum, the asexual state of Pseudallescheria boydii, is increasingly recognized as an opportunistic pathogen. We report a case of prosthetic valve endocarditis caused by this organism that developed in a patient following cardiac surgery.

Left ventricular apical infection and rupture complicating left ventricular assist device explantation in 2 women with postpartum cardiomyopathy

Postpartum cardiomyopathy is rare form of cardiac failure, with the potential for cardiac function to recover to normal. When medical therapy fails to control symptoms or haemodynamic stability, circulatory support with a ventricular assist device may be considered as a bridge to cardiac transplantation. We describe 2 patients with severe postpartum cardiomyopathy, in whom cardiac function recovered sufficiently during mechanical circulatory assistance to enable device explantation. Bacteremia during device support was treated with chronic suppressive antibiotics, yet after cannula explantation and ventricular repair, residual infection led to destruction of the primary repair, with formation of a left ventricular pseudoaneurysm. This is a complication of device support not previously reported. Surgery was necessary to repair the infected ventricular cannula site. Both patients recovered; however one patient developed recurrent cardiomyopathy 4 months later.

Infective endocarditis resulting in rupture of sinus of valsalva with a rupture site communicating with both the right atrium and right ventricle

This report describes a patient with a rupture of the noncoronary sinus of Valsalva caused by erosion of its wall by a large right atrial vegetation not attached to the tricuspid valve without aortic valve involvement. The rupture site was located right posterior to the tricuspid septal leaflet and communicated both with the right atrium and the right ventricular inflow tract, resulting in a significant left-to-right shunt leading to severe right heart failure and shock. The diagnosis was made by transthoracic and transesophageal echocardiography. To our knowledge no similar case has been reported in the literature.

Clostridium fallax associated with sudden death in a 16-year-old boy

Clostridial myonecrosis or gas gangrene occurs most frequently in contaminated wounds following trauma or surgery. It is caused by a wide variety of Clostridium species, the most common being Clostridium perfringens. Spontaneous, non-traumatic clostridial myonecrosis is uncommon and is usually associated with gastrointestinal and haematological malignancy, diabetes mellitus and peripheral vascular disease. The case of a previously healthy 16-year-old boy with acute onset of gastrointestinal symptoms, who died of bacterial sepsis without apparent preceding trauma, is presented here. Clostridium fallax was identified as the most probable causative agent. As far as is known, this is the first report of fatal sepsis in humans due to C. fallax, which has been described only rarely as a cause of gas oedema in animals.

E. Coli Sepsis Induces Profound Mechanoenergetic Inefficiency in the Porcine Left Ventricle

Myocardial dysfunction is believed to be a central part of septic multiorgan manifestations. The aim of the present study was to assess whether E. coli sepsis in an in vivo model would induce a dysfunction in the relationship between mechanical work and energy consumption in the left ventricle (LV). Accordingly, we measured hemodynamics, left ventricular pressure-volume area (PVA), and myocardial oxygen consumption (MVo2) in deeply anesthetized pigs. Eight pigs received 2.0 +/- 0.5 x 10(9) E. coli bacteria intravenously, and seven served as controls. Compared with baseline and the control group, no alternations were observed in LV diastolic function or indices of contractility in the septic group. The MVo2-PVA relationship was highly linear in both groups (all r2 = 0.96-0.99). At 5 h, the y-axis intercept of the MVo2-PVA relationship (nonmechanical MVo2) had increased in the sepsis group by 70% compared with baseline (P = 0.004) and by 60% compared with the control group (P = 0.003). Contractile efficiency (the inverse of the MVo2-PVA slope) remained unchanged over time and between groups. The study demonstrates a profound increase in nonmechanical oxygen consumption during E. coli sepsis in the LV.

Cardiac Aspergillosis with pedunculated mass in the left ventricle

Immunosuppression can allow organisms that are not usually pathogenetic to cause disease; under such circumstances, Aspergillus species frequently form large masses of fungal elements. We describe the case of a 12-year-old girl with hematologic remission of leukemia. She had a left ventricular pedunculated mass that was detected by echocardiographic study; at surgery, the presence of Aspergillus terreus was confirmed.

Interventricular hydatid cyst with atrioventricular block: a case report

Hydatid cyst in the heart is rare, occurring in about 3% of human echinococcosis. A 21-year-old woman was admitted to hospital with a third degree atrioventricular block. Echocardiography showed a cystic mass with a diameter of 2.5 cm within the interventricular septum. Serologic testing for Echinococcus was clearly positive, and hence cardiac surgery was planned. Sterilization of the cystic cavity was achieved by injecting formaldehyde solution in the cavity before cystectomy. Definitive pacemaker implantation was necessary before discharge. Cardiac hydatid cysts constitute an indication for surgery which is necessary to prevent potentially lethal complications such as cystic rupture with embolic phenomena and anaphylactic shock.

Scedosporium apiospermum (Pseudallescheria boydii) endocarditis

Scedosporium apiospermum, the asexual state of Pseudallescheria boydii, is increasingly recognized as an opportunistic pathogen. We report a case of native valve endocarditis due to this organism that developed in an elderly patient following a prolonged hospitalization. Literature on endocarditis caused by S. apiospermum and P. boydii is reviewed.

Right ventricular endocarditis due to infection of pacemaker apparatus

This article describes an unusual case of endocarditis in a 73-year-old man with a permanent pacemaker. Echocardiography revealed vegetations in the right ventricle below the tricuspid valve only, and he required open heart surgery for removal of the pacemaker system. This case demonstrates the potentially protracted course of infective endocarditis many years after pacemaker insertion. It also emphasizes the importance of echocardiography in diagnosing right ventricular vegetations; and the need for total replacement of the endocardial pacing system whenever it becomes infected.

Salmonella endocarditis of a ventricular aneurysm: a case report and review of the literature

A 63-year-old man with salmonella endocarditis of a ventricular aneurysm is presented. The patient had a documented apical aneurysm with mural thrombus and left ventricular dysfunction following a previous myocardial infarction. His condition was unresponsive to maximal medical therapy and was cured by surgery. A review of the English-language literature revealed that only two other published cases of nonvalvular salmonella endocarditis resulted in patient survival. This report underscores the importance of suspecting a cardiovascular origin in cases of salmonella bacteremia to avoid delay in diagnosis and surgical intervention in this deadly condition.

Postmortem blood cultures. Evaluation of separate sampling of blood from the right and left cardiac ventricle

Postmortem blood cultures were obtained by separate puncture of the right and left side of the heart during autopsy of 18 patients with solid cancer and 26 patients with non-neoplastic diseases. Concordant isolates were obtained from the right and left side in six patients (14%, 95% confidence limits: 5-28%). Growth was unilateral in 7 patients and cardiac aspirates were sterile in 31 patients (70%, 95% CL: 55-83%). One patient had been treated for Staphylococcus aureus bacteraemia and eight patients had negative premortem blood cultures. Separate culture of blood from the right and left side of the heart may add to the information gained by postmortem blood culture.

Retinal hemorrhages from septic emboli in a patient with a ventricular false chorda

PURPOSE

To demonstrate ophthalmic findings of bacterial endocarditis in a patient with a cardiac structural anomaly and to illustrate the potential usefulness of transesophageal echocardiography in the examination of such patients.

METHODS

We examined a patient with bacteremia who had white-centered retinal hemorrhages. Complete clinical, laboratory, and echocardiographic evaluations were performed.

RESULTS

Streptococcal bacteremia was proven and, by using transesophageal echocardiography, a ventricular false chorda was demonstrated.

CONCLUSIONS

Patients with white-centered retinal hemorrhages should undergo thorough systemic examinations. In this unusual case of such hemorrhages caused by bacteremia in a patient with a ventricular false chorda, modern, high-resolution transesophageal echocardiography played an important role in confirming the diagnosis.

Isolated apical intracavitary left ventricular abscess in a normal heart: a rare complication of Streptococcus milleri endocarditis

A 31-year-old patient without past history of cardiac disease presented with an atypical form of Streptococcus milleri endocarditis. The disease progressed in an unusually aggressive manner, with abscess formation in the apex of the left ventricular cavity. The cardiac valves functioned normally and were not affected by the disease.

Infective endocarditis of an interventricular patch caused by Acinetobacter haemolyticus

A case of infective endocarditis caused by Acinetobacter haemolyticus affecting and interventricular patch is reported. The patient, a 21-year-old man with a Fallot's tetralogy who had undergone cardiovascular surgery several years before, received imipenem and gentamicin for 6 and 4 weeks respectively and showed a good response without needing surgical treatment. Endocarditis by Acinetobacter species is very unusual and, to our knowledge, this is the first reported case of infective endocarditis caused by A. haemolyticus. As the clinical characteristics and the response to antibiotics appear to be similar to those reported for infective endocarditis by Acinetobacter lwoffi, prosthetic infective endocarditis by A. haemolyticus is apparently not always an indication for surgical treatment.

Chloride dependence of pH modulation by beta-adrenergic agonist in rat cardiomyocytes

The effects of beta-adrenergic agonists on pHi were studied on single ventricular myocytes isolated from adult rat heart and loaded with the acetoxymethyl ester (AM) form of the pH indicator SNARF-1. In modified Krebs' solution containing 20 mmol/L HEPES and 4.4 mmol/L HCO3-, isoproterenol (1 mumol/L) caused a significant decrease of steady-state pHi from 7.20 +/- 0.02 to 7.13 +/- 0.02 (mean +/- SEM) within 2 minutes. This acidification, which was also observed in myocytes that were preloaded with the Ca2+ chelator BAPTA and superfused with nominally Ca(2+)-free solution, was blocked by propranolol as well as by the specific beta 1-antagonist CGP 20712 A but not by the beta 2-antagonist ICI 118,551. Forskolin (10 mumol/L) induced a similar reversible decrease of pHi (average decrease, 0.11 +/- 0.02 pH unit). Furthermore, adenosine (100 mumol/L) substantially attenuated the isoproterenol-induced decrease of pHi. The effect of isoproterenol was not prevented by inhibitors of the Na(+)-H+ antiport, amiloride (1 mmol/L) and 2-N,N-hexamethylene amiloride (20 mumol/L). On the other hand, blockers of Cl- transport mechanisms, DIDS (200 mumol/L) and probenecid (100 mumol/L), inhibited this acidification, Isoproterenol also failed to induce a decrease of steady-state pHi in myocytes incubated in Cl(-)-free medium. Rather, the initial rate of rise of pHi observed on removal of external Cl- ions was significantly increased in the presence of isoproterenol or dibutyryl cAMP. Because the alkalinization induced by removal of Cl- ions is mainly due to reversal of the Cl(-)-HCO3- exchanger, the augmentation of this initial rate of pHi rise directly points to a beta-adrenergic stimulation of the exchanger. Furthermore, the pHi recovery following NH4Cl exposure was accelerated by isoproterenol in the presence of probenecid, indicating that the Na(+)-HCO3- cotransport and/or the Na(+)-H+ antiport also could be activated.(ABSTRACT TRUNCATED AT 250 WORDS)

Innervation of the heart and its central medullary origin defined by viral tracing

The vagus nerve exerts a profound influence on the heart, regulating the heart rate and rhythm. An extensive vagal innervation of the cardiac ventricles and the central origin and extent of this innervation was demonstrated by transynaptic transport of pseudorabies virus with a virulent and two attenuated pseudorabies viral strains. The neurons that innervate the ventricles are numerous, and their distribution within the nucleus ambiguus and dorsal motor nucleus of the vagus is similar to that of neurons innervating other cardiac targets, such as the sino-atrial node. These data provide a neuroanatomical correlate to the physiological influence of the vagus nerve on ventricular function.

Resection of infected ventricular aneurysm (Salmonella) following septic saddle embolus

Bacterial infection (Salmonella enteritidis) of left ventricular true and false aneurysm in a 62-year-old man was followed by septic saddle embolus. The septic saddle embolus was removed and the aneurysm was later resected with coronary bypass grafting. The patient is alive with satisfactory function over 5 years postoperatively.

Left ventricular mural bacterial endocarditis: diagnosis by transesophageal echocardiography

An unusual case of staphylococcal endocarditis with a vegetation attached to the left ventricular myocardium is described. No valvular vegetations are present. The diagnosis was made by transesophageal echocardiography. The patient had no chronic debilitating disease, nor was she immunosuppressed.

Cardiac myocytes and dendritic cells harbor human immunodeficiency virus in infected patients with and without cardiac dysfunction: detection by multiplex, nested, polymerase chain reaction in individually microdissected cells from right ventricular endomyocardial biopsy tissue

Two hundred fifteen patients infected with human immunodeficiency virus (HIV) participated in a prospective longitudinal study of HIV-related heart disease. Evaluation included signal-averaged electrocardiography and echocardiography. Fifteen patients underwent endomyocardial biopsy, 5 had cardiovascular symptoms and 10 did not. Cardiac myocytes or dendritic cells were prepared by individual cell microdissection to sort them from other cell types such as interstitial cells or circulating blood elements. HIV proviral sequences were amplified in samples of 15 to 20 cells of each type by multiplex, nested, polymerase chain reaction and hybridized to 32P-labeled probes specific for regions within the gag and pol genes of HIV-1. The results showed the presence of HIV sequences in myocytes of 2 of 5 patients with cardiac symptoms and in 6 of 10 without. Thus, symptomatic HIV cardiomyopathy did not appear to be a direct consequence of the virus on myocardial cells. In dendritic cells, HIV sequences were detected in 5 of 5 patients with cardiac symptoms and in 8 of 10 with apparently normal ventricular function. Furthermore, dendritic cells were somewhat more numerous in the myocardium of symptomatic than asymptomatic patients. Our studies are the first to directly detect the HIV genome in purified cardiac myocytes from patients with and without cardiac dysfunction. Our findings do not support a direct role of the virus in myocardial dysfunction. However, the results do suggest that the interstitial dendritic cells may be involved in some manner in the development of cardiac dysfunction observed in HIV-infected patients.

[Virological and morphological results in patients with congestive cardiomyopathy (author's transl)]

In 30 patients with congestive cardiomyopathy, right ventricular biopsies were performed. The biopsy material was investigated by virological and morphological methods. In all cases it was impossible to isolate viruses from the right ventricular myocardium, corresponding to the lack of infiltrative changes as shown by morphology. Results point against a direct causative role of viruses in the genesis of congestive cardiomyopathy.

Chronic cryptic Q-fever infection of the heart

Evidence of chronic Coxiella burneti infection of the heart, a disease previously considered peculiar to patients with valvular heart-disease, was found in a patient during routine serological tests before resection of a ventricular aneurysm and also by isolation of the rickettsia from the resected tissue. The patient had no symptoms or signs of Q-fever endocarditis and none of the laboratory evidence usually associated with it.

Determination of site of infection in endocarditis

Medical-surgical treatment of antibiotic refractory endocarditis requires determination of the site of infection, which is not always possible with conventional cardiac catheterization. The cases of two patients with right-sided endocarditis who survived after combined medical-surgical therapy are presented. One had persistent Pseudomonas aeruginosa bacteremia and three possible sites of infection. Multiple quantitative blood cultures proximal and distal to each suspected site indicated the pulmonary valve alone was infected. The second had sustained bacteremia with three enteric organisms and no apparent valvular abnormality. Quantitative cultures excluded the abdomen as the continuing source of bacteremia and suggested the tricuspid valve was infected. This was confirmed by a second catheterization using multiple cultures in conjuction with dye dilution studies, intracardiac phonocardiography, and angiography. These bacteriologic and cardiologic techniques may be especially useful in detecting right-sided endocarditis and may also be helpful in detecting concomitant infection of both sides of the heart.

Coxsackie viral infection of human myocardium

The myocardiu m of a young patient who had clinically established cardiomyopathy and suspected Coxsackie virus B4 infection was studied. Coxsackie B4 viral antigen was found in the ventricular and atrial myocardium by specific immunofluorescent antibody staining. Histologic examination revealed varying degrees of myocardial damage. Interstitial fibrosis and edema, swelling and deterioration of hypertrophic muscle fibers, connective tissue proliferation, stasis of small coronary blood vessels, atrophy of myocardial fibers with pyknosis of nuclei, and lytic deterioration were observed. Electron microscopic examination showed portions of the Z bands to be either widened or displaced into the sarcomere. Adjacent cell membranes in the region of the intercalated disc in the myocardium of both the ventricle and the atrium were separated, forming large gaps. Morphologic changes were most pronounced in the atrium adjacent to the mitral valve, in which the mitochondria were grossly swollen, and large vesicles were present in the sarcoplasm. The pathologic changes found in the myocardium of all chambers of the heart apparently were due to Coxsackie B4 viral infection.

Pathogenicity of stable L-phase variants of Staphylococcus aureus: failure to colonize experimental endocarditis in rabbits

Endocarditis was induced in the rabbit by the placement of a polyethylene catheter in the right heart. The catheter was filled with stable L-phase variants of Staphylococcus aureus to determine if the variant form would colonize the damaged endocardium and produce further tissue injury similar to that produced by the vegetative bacterial phase. No L-phase variants were recovered from cultures of blood or vegetations, although pure cultures of L-phase variants were obtained from all catheters, including one in place for 70 days. The vegetations were grossly similar in control animals with sterile media in the catheters and animals with catheters containing L-phase variants, although polymorphonuclear leukocytes and eosinophils were more frequently found in vegetations from animals inoculated with L-phase variants. Endocarditis was also induced in animals with vegetative S. aureus and then treated with penicillin G. Blood cultures in hypertonic media often grew vegetative S. aureus when there was no growth in routine media, but no L-phase variants were detected. Vegetative S. aureus, but not wall-defective variants, were isolated from vegetations of all treated animals.