Conservative management of a prosthetic valve thrombosis--report of a successful case

Management of prosthetic valve thrombosis with unfractionated heparin

BACKGROUND

Prosthetic valve thrombosis (PVT) is a severe and life-threatening complication. Surgery and thrombolytic therapy (TT) carry a high risk, and in several circumstances, optimal anticoagulation with unfractionated heparin (UFH) infusion may be an alternative treatment. This study aimed to assess the results of UFH in patients diagnosed with both obstructive and non-obstructive PVT.

METHODS

This observational retrospective study enrolled patients who had contraindications for TT and surgery underwent UFH therapy.

RESULTS

A total of 136 patients were enrolled [male: 55 (40.4%), mean age: 50.3 ± 14.6 years] in the study. In the successful group, 66 patients (48,5%) showed >75% regression in the thrombus burden without facing death or major non-fatal complications.In the unsuccessful group, 56 had less than a 50% reduction in thrombus load and 14 (10.3%) suffered major complications. The presence of obstruction (27.1% vs. 12.1%; p = 0.028), thrombus area 1.1 cm2 vs. 0.8 cm2; p = 0.005] and the duration of UFH treatment (15.1 vs. 11.8 (days); p = 0.005) were significantly higher in the unsuccessful UFH group.In multivariate regression analyses the presence of obstruction (RR: 3.088, p = 0.020), increased thrombus area (RR: 2.400; p = 0.015), and increased duration of UFH therapy (RR: 1.073 95%, p = 0.012) were identified as independent predictive parameters for a failed UFH therapy.

CONCLUSIONS

This study suggests that UFH therapy may be considered a relatively beneficial treatment strategy for some patients with PVT. The most significant factors affecting success are the obstructive nature and area of the thrombus.

Clinical Features and Survival Analysis of Patients after Mechanical Heart Valve Replacement, with an Emphasis on Prosthetic Valve Thrombosis

BACKGROUND

Valvular heart diseases are highly prevalent in the world, and surgical valve replacement has improved patients' survival.

OBJECTIVES

To describe clinical and laboratory data of patients undergoing mechanical valve replacement, and to determine the incidence of prosthetic valve thrombosis (PVT).

METHODS

Retrospective cohort study with a follow-up of up to nine years. The study variables were collected from conventional and electronic medical charts. Statistical calculations were performed using the Jamovi software version 1.2.2.; a p<0.05 was considered statistically significant. Kaplan Meier curves were constructed, and Cox regression analysis was performed for analysis of factors related to mortality.

RESULTS

A total of 473 patients were included, mean age of 46.9 ±11.3 years. Rheumatic disease was the most common etiology. In a mean follow-up period of 4.43 years, mortality rate was 16.1%. Patients with aortic prosthesis showed higher survival than patients with double implant (mitral and aortic) (p=0.026). Of the factors adjusted for mortality, only functional class and chronic renal failure showed statistically significant association. The incidence of PVT was 0.24/100 patients/year, and the first event occurred more than 1000 days after the implant. Smoking and pannus formation were significantly associated with PVT. No differences were found in INR variability between patients with and without thrombosis by prosthetic position, but significant differences were found in INR before thrombosis as compared with patients without thrombosis (INR= 2.20 [1.80-2.20] vs. 2.80 [2.20-3.40]; p= 0.040). The incidence of stroke and bleeding was 4.4% and 5.2% respectively.

CONCLUSIONS

The study population was young, and rheumatic valve disease was common in this group. The prevalence of PVT was similar to that described in the literature, despite the low income and low educational level of our sample.

Thrombolytic treatment of prosthetic valve thrombosis: a study using Urokinase

OBJECTIVE

We analysed the efficacy and safety of thrombolytic therapy with urokinase in patients with prosthetic valve thrombosis.

METHODS

Twenty-three patients with valve thrombosis received thrombolytic treatment using urokinase. First, a 250,000 IU intravenous bolus injection was administered as a loading dose, followed by intravenous infusion of 100,000 IU/h for 10 h and anticoagulation with low molecular weight heparin every day. The maximum treatment time was 5 days, i.e., until the transvalvular pressure gradient was normal or close to normal. Transthoracic echocardiography (TTE) was used every 12 h to monitor whether the thrombus was reduced and whether there was haemodynamic improvement. Routine blood tests, the prothrombin time (PT), international normalized ratio (INR) and complications were observed every day.

RESULTS

Sixteen (69.6%) patients were successfully treated with thrombolytic therapy: 2/2 (100%) aortic valves and 14/21 (66.7%) mitral valves. The partial success rate of this study was 13.0% (3/23). Four patients did not show any improvement in haemodynamics. Two cases had slight urine haemorrhage. One patient died of severe cerebral haemorrhage and shock. The overall mortality was 13.0% (3/23), including two patients who died after subsequent surgery.

CONCLUSION

Urokinase is more convenient and successful in the treatment of PVT. More experience may make TT the optimal treatment for PVT, especially in high-risk surgical situations.

Coronary Embolism and Myocardial Infarction: A Scoping Study

Coronary embolism is a cause of acute myocardial infarction (AMI)in which obstructive foci enter the coronary circulation, block normal blood flow and precipitate ischemia. Precise studies focusing on patient population affected, pathophysiological mechanisms, and treatment strategies are scanty, in spite of a reported prevalence estimated at 2.9%. As the understanding of myocardial infarction without evidence of coronary artery disease continues to grow, an in-depth review of this previously seldomly reported subtype of coronary ischemia was in order. Patients suffering coronary embolism are 15 to 20 years younger than traditional AMI patients with a slight predominance towards male sex, which resembles the gender data of the populations affected by non-traditional myocardial infarction in published reports. While the expected prevalence rate of cardiovascular disease risk factors such as hypertension and hyperlipidemia are present, this population also has a relatively high prevalence of atrial fibrillation and valve pathology, especially endocarditis. Initial presentation is indistinguishable from other causes of myocardial infarction however fever is commonly present, when endocarditis with valvular involvement is the primary cause of the coronary embolism. Mechanical thrombectomy is the mainstay of treatment, followed by percutaneous coronary intervention. Mortality is the highest in patients who do not receive targeted treatment for the coronary embolism, particularly if only antimicrobial agents or anticoagulation without thrombolytic agents are employed. The unique features of coronary embolism highlighted in this historical study justify further examination in contemporary patient populations.

Presentation, management and outcome of heparin-induced thrombocytopenia after valvular heart surgery

OBJECTIVES

The use of heparin exposes patients to heparin-induced thrombocytopenia, which is a challenging issue for both diagnosis and patient management. We sought to describe the clinical presentation, management and outcome of a series of patients diagnosed with heparin-induced thrombocytopenia after heart valve surgery.

METHODS

All consecutive patients diagnosed with heparin-induced thrombocytopenia during the postoperative period of heart valve surgery over a 6-year period were prospectively enrolled in a single-centre registry. Clinical and biological data were collected. In-hospital and mid-term outcomes were assessed. Information regarding the occurrence of all medical events including death, recurrence of thromboembolic events and/or thrombocytopenia was collected.

RESULTS

We identified 93 patients (incidence proportion = 2.8%). Most patients (82%) were asymptomatic with isolated thrombocytopenia at the time of diagnosis. The other main circumstance of diagnosis was the occurrence of thromboembolic events in 17 patients (6 strokes, 10 prosthetic valve thrombosis and 1 peripheral embolic event). The in-hospital mortality rate was 1%. No thrombolysis, interventional procedure or redo surgery was performed. Danaparoid sodium was used as heparin replacement therapy in most cases (96%) and leading to complete and uneventful thrombus resolution in all cases with only one possibly related major bleeding complication. During a mean follow-up of 36 ± 20 months, no patient presented recurrence of any heparin-induced thrombocytopenia-related complication.

CONCLUSIONS

In this contemporary series of patients, heparin-induced thrombocytopenia incidence was low and isolated thrombocytopenia was the most frequent presentation. Conservative management with early diagnosis and substitutive anticoagulation therapy introduction was associated with a low rate of clinical events and a remarkably good outcome with a low mortality rate.