Frequency and significance of M-mode echocardiographic evidence of mitral valve prolapse in clinically isolated pure mitral regurgitation: analysis of 65 patients having mitral valve replacement

To assess the reliability of M-mode echocardiographic patterns of mitral valve prolapse (MVP) (echo MVP) in detection of morphologic evidence of MVP (morphologic MVP), operatively excised mitral valves and corresponding M-mode echocardiograms from 65 patients with chronic, severe, isolated, pure mitral regurgitation (MR) were studied. Of the 65 patients, 45 (69%) had echo MVP (either holosystolic or mid-to-late systolic prolapse patterns on preoperative M-mode echograms) and 42 (93%) of them had morphologic MVP; of the 3 without morphologic MVP, 2 had ruptured chordae tendineae from infective endocarditis and 1 had papillary muscle dysfunction from atherosclerotic coronary heart disease. Of the 20 patients without echo MVP, 14 (70%) had no morphologic MVP (9 had papillary muscle dysfunction from coronary heart disease, 4 had infective endocarditis on previous normal valves and 1 had rheumatic heart disease). Of the 48 patients with morphologic MVP, 42 (88%) had echo MVP and most had considerably dilated mitral anulae; the other 6 had ruptured chordae tendineae with less degrees of anular dilatation. Of the 17 patients without morphologic MVP, 3 had echo MVP (coronary artery disease in 1 and infective endocarditis on a previous normal valve in 2); of the 14 with neither echo nor morphologic MVP, 9 had papillary muscle dysfunction from coronary artery disease, 4 had infective endocarditis on previously normal valves and 1 had rheumatic heart disease. The patients with very dilated mitral anuli and leaflet areas generally had holosystolic (hammocking) patterns on echo; the patients with small anuli and leaflet areas usually had mid-to-late systolic (buckling) prolapse patterns.     

Transthoracic echocardiography (TTE): sufficiently sensitive screening test for native valve infective endocarditis (IE)

We recently reviewed our experience with paired transthoracic echocardiogram (TTE) and transesophageal echocardiogram (TEE) studies for the diagnosis of native valve infective endocarditis. In patients with normal heart valves, we demonstrated that a normal TTE effectively rules out infective endocarditis and a TTE is unnecessary. In patients with abnormal heart valves, a TEE did not enhance the diagnostic yield in most patients (12/15). We reviewed 87 paired TTEs and TEEs, that is, TEE with a preceding TTE performed for the evaluation of native valve IE. Of 87 paired echocardiograms, 72 of 87 had normal TTEs and TEEs, with no evidence of a vegetation indicative of infective endocarditis. A total of 15 of 87 TTEs had thickened/calcified valves without a definite vegetation. Of these, only 3 of 15 were subsequently shown to have a vegetation indicative of endocarditis by TEE. In patients with possible native valve infective endocarditis, before blood culture results are known, a negative TTE was sufficiently specific to rule out native valve infective endocarditis. Our data showed that the negative predictive value of a normal TTE in the evaluation of possible native valve endocarditis is 90% or greater. In those with some valve abnormality (ie, thickened/calcified heart valves), subsequent TTE did not materially increase vegetation detection.     

Staphylococcus capitis endocarditis due to a transvenous endocardial pacemaker infection: case report and review of Staphylococcus capitis endocarditis.

OBJECTIVES: Newer microbiologic methods to determine the species of coagulase-negative staphylococci (CoNS) have evolved which have shown that most endocarditis due to CoNS is caused by Staphylococcus epidermidis, and far fewer by Staphylococcus warneri and Staphylococcus lugdunensis. METHODS: The recent opportunity to successfully treat a patient with methicillin-resistant Staphylococcus capitis endocarditis secondary to an infected transvenous pacemaker led to a review of the literature relating to S. capitis endocarditis. RESULTS: Thirteen previously recorded patients were identified. Twelve (86%) patients were male. Ten had endocarditis associated with a native valve, two with prosthetic valves and one with a transvenous pacemaker. Mortality was low in all 14 cases (including this case report) with only two deaths; one in a patient with a native valve and the other with a prosthetic valve. Four of the isolates were methicillin resistant but sensitive to vancomycin, which was used in the treatment of eight patients. Those patients with prosthetic cardiac devices appear to do better when the devices are surgically removed. CONCLUSIONS: CoNS as a cause of endocarditis appears to be increasing and the current ability to determine the species of these organisms should elicit the epidemiology, clinical characteristics and biomolecular mechanisms involved in the induction of valvular disease.     

Endocarditis due to Trichosporon beigelii: in vitro susceptibility of isolates and review

Infection with Trichosporon beigelii is an uncommon cause of endocarditis. Of the eight cases of T. beigelii endocarditis that have been reported (one herein and seven previously), six involved prosthetic heart valves and two involved native heart valves. The clinical manifestations of this infection included embolization of the superficial femoral artery or of the bifurcation of the posterior tibial and peroneal arteries in three of these patients (two with prosthetic valve and one with native valve endocarditis). In seven of the eight reported cases, blood cultures were positive for the organism. Although clinical isolates of the organism are generally reported to be susceptible to amphotericin B, isolates can vary in their sensitivities to antifungal agents in vitro depending on the methodology used, and clinical response to therapy with antifungal agents in a regimen that includes amphotericin B is generally poor. Only two of six patients who were treated with antifungal agents survived endocarditis caused by T. beigelii and were apparently cured; one of these patients was also managed surgically with valve replacement. Infection with T. beigelii should be considered in the differential diagnosis of endocarditis in immunocompetent patients, particularly those who have a prosthetic heart valve. Rapid, aggressive therapy may be necessary to eradicate this organism.     

Infective endocarditis--analysis of 116 surgically and 26 medically treated patients

We have reviewed 116 cases of bacterial endocarditis treated surgically and 26 cases treated medically since 1973. There were 123 patients with native valve endocarditis and 19 patients with prosthetic valve endocarditis. Overall, the left-sided valves were infected most frequently. There were 10 cases with right-sided valves involved. Multiple valves were infected in 6 patients. There were 6 perioperative deaths in the surgical group. The most common cause of death was multi-organ failure associated with uncontrollable sepsis. The overall operative mortality for active endocarditis was 7.7% (4/55), and for healed endocarditis, 3.3% (2/61). For active native valve endocarditis, the mortality was 4.2% (2/48), for healed native valve endocarditis, 3.6% (2/55), for active prosthetic valve endocarditis, 28.6% (2/7), and for healed prosthetic valve endocarditis, 0%. There was no difference in the operative mortality between active native valve endocarditis and healed native valve endocarditis. The mortality of active prosthetic valve endocarditis was significantly higher than that of active native valve endocarditis (p less than 0.01). Of the 26 patients treated medically, 7 died during the initial hospitalization. The major factor related to mortality in the medically treated patients was persistent sepsis (four patients), and congestive heart failure (three patients). The overall mortality of the medical group for active valve endocarditis was 15% (3/20), and for active prosthetic valve endocarditis, 67% (4/6). We conclude that patients with infective endocarditis with significant valve lesions who are unresponsive to medical therapy should be considered for urgent surgery.     

Malplacement of a pacemaker lead--a rare cause for aortic valve endocarditis

Infective endocarditis of native valves following pacemaker implantation is rare but can be associated with serious complications, approaching a mortality of up to 25%. Recent publications report a frequency of pacemaker related endocarditis between 0.5 and 7%. Due to anatomical reasons the tricuspid valve is mostly affected in these patients, with involvement of the left heart valves usually secondary. We report an incidence of native aortic valve endocarditis due to a misplaced pacemaker lead into the left heart.     

Native aortic valve vegetative endocarditis with Cunninghamella.

Cunninghamella bertholletiae is a rare Mucor species that is seldom the cause for endocarditis of prosthetic heart valves. It is even a more uncommon cause of endocarditis of native heart valves. We present a case of Cunninghamella endocarditis of a native aortic valve in an immuno-compromised patient, diagnosed from tissue culture obtained at the time of surgery. There have only been two other reported cases of native valve endocarditis with a Mucor species, and in those cases, the diagnoses were made post-mortem.     

Staphylococcus hominis native mitral valve bacterial endocarditis (SBE) in a patient with hypertrophic obstructive cardiomyopathy

There are several species of coagulase-negative Staphylococci (CoNS) that are part of the normal skin flora and are relatively noninvasive/low virulence organisms. CoNS are important pathogens in patients with prosthetic devices and are the most common pathogen associated with prosthetic valve endocarditis. CoNS native valve infective endocarditis (IE) is rare. Patients with hypertrophic obstructive cardiomyopathy and an outflow pressure gradient greater than 30 mm Hg are predisposed to IE. There has been only one reported case of non-mitral valve IE due to CoNS in a patient with hypertrophic obstructive cardiomyopathy. To the best of our knowledge, we report the first case of Staphylococcal hominis mitral valve endocarditis in a patient with hypertrophic obstructive cardiomyopathy.     

Complications of prosthetic heart valves

Treatment of native valvular heart disease has resulted in an increasing number of patients with prosthetic valves. Although an improvement over the diseased native valve removed at surgery, prosthetic valves have suboptimal hemodynamics; mechanical valves require anticoagulation and tissue valves wear out over time. Serious complications of prosthetic valves occur at a rate of about 2% to 3% per patient-year. Complications include thromboembolism, prosthesis-patient mismatch, structural valve dysfunction, endocarditis, and hemolysis. Prosthetic valve endocarditis is a lethal disease with mortality rates of 50% to 80% even with appropriate therapy. Echocardiography now provides detailed information on valve function and hemodynamics, allowing early detection of complications. Many of these complications can be prevented by choosing the optimal valve at the time of surgery, rigorous control of anticoagulation and adherence to established anticoagulation guidelines, dental hygiene and endocarditis prophylaxis, and periodic echocardiographic monitoring by a cardiologist.     

Native double-valve endocarditis by Mycobacterium fortuitum following percutaneous coronary intervention

Infective endocarditis caused by atypical mycobacteria, especially Mycobacterium fortuitum, is rare. Most reported cases involve diseased valves or prosthetic heart valves. Only four cases of native valve endocarditis caused by this organism have been previously reported. Herein is reported a case of native valve endocarditis caused by M. fortuitum; the epidemiology and management of this rare cause of culture-negative endocarditis is discussed.     

Surgical aspects of endocarditis

Endocarditis represents a difficult medical problem that must occasionally be treated surgically. Constitutional symptoms of infection are important and are usually the reason that the patient seeks medical attention. Fever is the most common sign of infective endocarditis and a heart murmur, which changes in character or is new, is a significant hallmark. The diagnosis for infective endocarditis is made by high index of suspicion in a patient with valvular heart disease or a prosthetic heart valve and in the presence of fever and a cardiac murmur. A positive blood culture is the hallmark of the diagnosis. The absolute indications for operative intervention are congestive heart failure, unstable prosthetic valve, uncontrolled infection, and relapse after optimal therapy (prosthetic valve). Relative indications for operative intervention are perivalvular extension of the infection, staphylococcal infection of a prosthesis, persistent fever (culture negative), large vegetation, or relapse after optimal therapy (native valve). The principles of surgical management are to remove all infected tissue by thorough debridement back to normal tissue. This is combined with replacement of damaged valves and repair of associated defects. The mortality after operation for infective endocarditis is 15-20%. Late survival after operation for infective endocarditis on a native heart valve is 70-80% at 5 years. Survival falls to 50-80% at 5 years for surgery on an infected prosthetic heart valve.     

Staphylococcus capitis endocarditis: two cases and review of the literature

Coagulase negative staphylococci are the principal cause of prosthetic valve endocarditis but are a rare cause of native valve infections. However, the incidence of native valve endocarditis is increasing. Staphylococcus capitis is a coagulase negative staphylococcus with the capacity to cause endocarditis on native heart valves. Two cases of native valve endocarditis caused by S capitis are presented; both in patients with aortic valve disease. The patients were cured with prolonged intravenous vancomycin and rifampicin and did not need surgery during the acute phase of the illness. Five of the six previously described cases of endocarditis caused by this organism occurred on native valves and responded to medical treatment alone.


Keywords: Staphylococcus capitis; endocarditis; valvar disease; coagulase negative staphylococci     

Echocardiographic and clinical correlations in infectious endocarditis of the left heart

The echocardiographic features were correlated with the clinical findings and outcome in 35 patients with aortic and/or mitral valve endocarditis. There were 26 males and 9 females with a mean age of 38 years. The infection involved native valves in 27 patients and prosthetic valves in 8 patients. Echocardiographically, fourteen patients had involvement of native aortic valve. All patients in this group required surgical intervention, nine patients during antimicrobial therapy. Congestive heart failure was the clinical indication for valvular replacement. A patient died immediately after surgery from low cardiac output syndrome. Six patients had echocardiographic evidence of aortic and mitral valves involvement. A patient in this group expired before surgery, five underwent surgery because of progressive heart failure (aortic or aortic and mitral valves replacement). Seven patients showed lesions on native mitral valve (6 in this group had prolapse syndrome). A patient died from cerebrovascular embolus, two underwent surgery because of persistent infection and embolic events, four were successfully treated with medical therapy. Among patients with prosthetic valve endocarditis, four showed signs of valvular dehiscence and required surgical intervention, during antimicrobial therapy, from congestive heart failure; one patient expired from recurrent infection. The pathological findings correlated well with echocardiographic findings. Conclusions: in IE the localization of lesions by echo has prognostic significance: most patients with aortic valve or aortic and mitral valves endocarditis require early surgical intervention because of congestive heart failure. On the contrary, mitral valve involvement carries a better prognosis, requiring less frequently valvular replacement; the patients with echocardiographic signs of prosthetic valve dehiscence require urgent intervention.(ABSTRACT TRUNCATED AT 250 WORDS)     

Current profile of left-sided native valve endocarditis caused by coagulase-negative Staphylococcus

Coagulase-negative staphylococci are the most frequently isolated microorganisms in early prosthetic valve endocarditis. However, they rarely cause endocarditis in native valves. The profile of patients with left-sided native valve endocarditis by coagulase-negative staphylococci is unknown, because available data are scarce and outdated. We analyzed the epidemiological, clinical, radiographic, microbiological, and echocardiographic features and clinical course in 17 patients with this entity out of a total of 441 consecutive patients diagnosed as having endocarditis. The results show that left-sided native valve endocarditis caused by coagulase-negative staphylococci is more common than previously reported, can cause heart failure due to valvular involvement, often needs surgery, and is associated with high mortality.     

Q fever bioprosthetic aortic valve endocarditis (PVE) successfully treated with doxycycline monotherapy

Q fever is a zoonotic infection caused by Coxiella burnetii. The most common clinical manifestation of acute Q fever infection is as an atypical community-acquired pneumonia. The pulmonary findings are accompanied by extrapulmonary findings, most typically an increase in serum transaminases and splenomegaly. Because C. burnetii is difficult to culture, the diagnosis of Q fever is usually made serologically. The diagnosis of acute Q fever atypical community-acquired pneumonia is made by demonstrating a fourfold or greater increase in titer between acute and convalescent specimens or by demonstrating elevated immunoglobulin (IgM) (phase II) titers. Chronic Q fever is manifested as granulomatous hepatitis or more commonly as culture-negative endocarditis (CNE). Chronic Q fever (CNE) is a difficult diagnosis because of difficulty in culturing the organism from the blood and the vegetations with Q fever CNE are small or absent. The diagnosis of chronic Q fever CNE is based on serology. Such patients commonly have highly elevated IgM and IgG titers (phase I/II) titers. Chronic Q fever CNE may involve native or prosthetic heart valves. Q fever prosthetic valve endocarditis is rare compared with native valve Q fever endocarditis. Q fever prosthetic valve endocarditis usually requires valve replacement for cure. We present a case of chronic Q fever bioprosthetic aortic valve endocarditis that was successfully treated with doxycycline monotherapy that did not require aortic valve replacement.     

Stenotrophomonas maltophilia endocarditis: a systematic review

The disease characteristics, management, and outcome of Stenotrophomonas maltophilia endocarditis were evaluated by examining the reports on the subject identified through a comprehensive literature search. Twenty-three (17 male) cases of S.. maltophilia endocarditis were identified. Mean age was 41 +/- 15 years. All patients presented with fever. Prosthetic valves were involved in 12 (52%) cases. Among native valves, the aortic valve was most frequently involved (50%), followed by the tricuspid valve (36%). Twenty (87%) patients had underlying risk factors for the development of endocarditis, including prior valvular or congenital heart disease surgery (60%), intravenous drug abuse (32%), and infected intravascular lines (18%). The endocarditis was postoperative in 14 patients. Seventeen (74%) patients experienced complications including septic embolism (23%), cardiac abscesses (23%), and congestive heart failure (18%). A combination of two or more antibiotics was used in all cases except one. The frequently used antibiotics were aminoglycosides (59%), trimethoprim-sulfamethoxazole (48%), and penicillins (48%). One half of the patients required cardiac surgery, but the proportion of surgically treated cases was higher among prosthetic valve endocarditis (62%). Mortality was 39% and was equally distributed between patients with prosthetic and native valve endocarditis. The S. maltophilia endocarditis carries high complication and mortality rates. The antibiotic regimen should consist of a combination of multiple antibiotics guided by the sensitivity panel. Early surgery may be considered in patients not responding to antibiotic treatment and in those with prosthetic valve endocarditis.     

New approaches to the diagnosis and treatment of infective endocarditis: review of 100 consecutive cases

To assess the effect of our new, more aggressive approach to treating infective endocarditis, we retrospectively reviewed our recent experience with this disease. Between 1983 and 1989, we treated 100 patients with endocarditis, in 94 of whom the diagnosis was confirmed. Fifty-four (57%) of the 94 patients had native valve endocarditis, and the other 40 patients (43%) had prosthetic valve endocarditis. The patients' mean ages were 50 years for native valve disease and 58 years for prosthetic valve disease (p < 0.05). The male-to-female ratio was 4:1. Among the patients with confirmed endocarditis, 87 (93%) had significant underlying risk factors for endocarditis. Upon physical examination of the 94 patients, 16 (17%) were afebrile, 15 (16%) had negative blood cultures, and 26 (28%) had no cardiovascular symptoms or immunologic findings. Echocardiography was of limited value: its sensitivity was 56% for native valve endocarditis and 33% for prosthetic valve endocarditis. The ratio of affected valves was 5 aortic:4 mitral: 1 tricuspid in both forms of the disease. Viridans streptococcus was isolated in 23 (25%) of the confirmed cases, Enterococcus faecalis in 17 (18%), Staphylococcus aureus in 13 (14%), and coagulase-negative staphylococcus in 14 (15%). Gram-negative, anaerobic, and fungal organisms accounted for only 13 (14%) of the confirmed cases. The mean duration of intravenous therapy was 29 days. Twenty (37%) of the native valve patients and 16 (40%) of the prosthetic valve patients received antibiotics on an outpatient basis. Vancomycin was used in 44 (47%) of the cases, nafcillin or ampicillin in 40 (44%), and other beta-lactam agents in 9 (10%). The mean hospital stay was significantly longer for prosthetic valve endocarditis patients than for those with native valve disease (29 versus 23 days; p < 0.01). Cardiac catheterization was performed in 9 native valve patients (17%) and 6 prosthetic valve patients (15%). Valve surgery was performed in 33 native valve patients (61%) and 22 prosthetic valve patients (55%). Failure, defined as in-hospital death or recurrent endocarditis, accounted for 14 (28%) of the native valve cases (17% death and 11% relapse) and 8 (20%) of the prosthetic valve cases (10% death and 10% relapse), for an overall failure rate of 24%. The rate of failure was independent of the infecting pathogen or the type of antimicrobial therapy applied. Our experience verified that, in many patients with significant underlying risk factors, the diagnosis of endocarditis may be made on an empiric basis.     

Tricuspid stenosis in prosthetic valve endocarditis. Diagnosis by Doppler echocardiography

Valvular stenosis is an uncommon finding in bacterial endocarditis involving native cardiac valves. Prosthetic valve endocarditis, however, is more commonly associated with obstruction. Bioprosthetic cardiac valves may be particularly prone to this complication. A case of bioprosthetic tricuspid valve endocarditis with stenosis diagnosed by Doppler echocardiography and confirmed by operative findings is presented.     

Viridans streptococcal endocarditis: clinical, microbiological, and echocardiographic correlations

Infections caused by species within the viridans streptococci have been associated with different clinical characteristics. We studied 36 patients with viridans streptococcal endocarditis. Complications were seen in 10 (32%) of 31 patients with native valve endocarditis and four (80%) of five with prosthetic valve endocarditis and included death in two, valve replacement in six, persistent infection in three, emboli in two, and congestive heart failure in nine. Two-dimensional echocardiograms demonstrated vegetations in 26 (72%) of 36, flail mitral valves in seven, disruption of aortic valve prosthesis in one, and perivalvular abscesses in three (two Streptococcus sanguis I and one Streptococcus intermedius I). All twelve patients with native valve endocarditis who suffered complications had vegetations detected by two-dimensional echocardiography, whereas seven patients with native valve endocarditis without vegetations, as detected by two-dimensional echocardiography, had no complications (P = .03). We found no significant correlation between streptococcal species and clinical outcome. To confirm our identifications, we sent 16 identical viridans streptococcal endocarditis isolates to five institutions; only three of 16 were identified as the same species by all five institutions. We conclude that viridans streptococcal endocarditis can be associated with a virulent clinical course and that there is marked variability in species designations of individual strains by different laboratories.     

Clinical outcome and echocardiographic findings of native and prosthetic valve endocarditis in the 1990s

Prosthetic valve endocarditis is considered to be associatedwith a more severe prognosis than native valve endocarditis.Among other factors, inappropriate visualization of vegetationsin prosthetic valve endocarditis by transthoracic echocardiographyis responsible for this observation. Since the introductionof transoesophageal echocardiography into clinical practicethe diagnostic sensitivity and specificity of the detectionof vegetations located on prosthetic valves have been enhanced.Therefore we aimed to determine and compare the prognosis ofprosthetic valve endocarditis and native valve endocarditisin the era of this improved diagnostic approach. One hundred and six episodes of infective endocarditis in 104patients were seen at our institution between 1989 and 1993.Eighty patients (77%) had native valve endocarditis and 24 (23%)had late prosthetic valve endocarditis. In the latter grouptwo patients had recurrent infective endocarditis. Patientswith prosthetic valve endocarditis were older (mean age 64 vs54 years in native valve endocarditis; P<0.00l) and the majoritywas female (62% vs 38% in native valve endocarditis; P<0.001In prosthetic valve endocarditis, infection of a valve in themitral position predominated (65% vs 30% in native valve endocarditis;P<0.0l), whereas in native valve endocarditis more than halfthe cases had isolated aortic valve endocarditis (51% vs 27%in prosthetic valve endocarditis; P<0.01). In prostheticvalve endocarditis more cases were caused by Staphylococcusaureus (31% vs 14% in native valve endocarditis; P<0.08),whereas in native valve endocarditis the most frequent organismswere streptococci (29% vs l9% in prosthetic valve endocarditis;P<0.12). Differences in the clinical features of native valveendocarditis and prosthetic valve endocarditis could not befound except for a higher rate of embolism in native valve endocarditis(40% vs l9% in prosthetic valve endocarditis; P<0.05). Vegetationscould be detected by transthoracic echocardiography more frequentlyin native valve endocarditis (71% vs 15% in prosthetic valveendocarditis; P<0.0001). Transoesophageal echocardiographyvisualized vegetations in 95% of the episodes of native valveendocarditis and in 80% of the episodes of prosthetic valveendocarditis (P<0.09). Thus, the diagnostic gain by transoesophagealechocardiography was greatest in prosthetic valve endocarditis.Patients with native valve endocarditis had significantly largervegetations than patients with prosthetic valve endocarditis(P<0.05 for length, P<0.00l for width). The median timeto diagnosis was similar in native valve endocarditis and prostheticvalve endocarditis (31 vs 28 days). Surgery was performed in 74% of patients with native valve endocarditisand in 58% of those with prosthetic valve endocarditis; themedian time delay between the diagnosis of infective endocarditisand surgery tended to be shorter in prosthetic valve endocarditisthan in native valve endocarditis (45 vs 60 days). The in-hospitalmortality and the mortality during a follow-up of 22±10 months did not significantly differ between native valveendocarditis and prosthetic valve endocarditis (21% vs 17% 28%vs 25%). In summary in the era of transoesophageal echocardiography,late prosthetic valve endocarditis does not seem to carry aworse prognosis than native valve endocarditis. This can beattributed in part to the improved diagnostic accuracy achievedby transoesophageal echocardiography leading to comparable diagnosticlatency periods in both patient groups. Finally, better characterizationof vegetations on prosthetic valves by transoesophageal echocardiographyallows early lifesaving surgery in patients with prostheticvalve endocarditis.