Safety and Feasibility of Dental Evaluation in Patients Undergoing Heart Valve Replacement Surgery: Retrospective Analysis

Abstract

Background/Objectives: Although there is a general consensus that patients should have dental evaluation before heart valve surgery, data on the extent and complications of this evaluation are scarce. The objective was to analyze safety and feasibility of dental evaluation in patients undergoing heart valve surgery. Methods: A retrospective chart review of patients referred for dental evaluation prior to heart valve surgery in 2021–2023 was conducted. Demographic, medical, and dental data were recorded. The number and type of dental procedures and their complications were recorded, along with the number of appointments and the time required to achieve dental clearance for heart valve surgery. Results: One hundred and fifty-three patients were referred in the observed period. The predominant procedure was tooth extraction, accounting for 76 (49.7%) cases. Complications were recorded in 3 (1.9%) patients, with delayed bleeding being the most prevalent issue, occurring in 2 (1.3%) patients. The median time required to obtain dental clearance for cardiosurgical procedure was 1 day, with 124 (81%) patients obtaining clearance in a single appointment. No dental emergencies were observed during hospital admission for the cardiosurgical procedure. Conclusions: Our results suggest that dental evaluation before heart valve surgery can be conducted in a reasonable amount of time with a low complication rate and without the need to delay cardiosurgical procedures.

1. Introduction

Dental evaluation before heart valve surgery has been recommended as a standard of care for a long time. According to the guidelines of the European Society of Cardiology (ESC), it is “strongly recommended that potential sources of dental sepsis should be eliminated at least 2 weeks before implantation of a prosthetic valve or other intracardiac or intravascular foreign material, unless such procedures are urgent” [1]. The American Heart Association’s guidelines suggest the following: “A careful preoperative dental evaluation is recommended so that required dental treatment may be completed whenever possible before cardiac valve surgery or replacement or repair of congenital heart disease. Such measures may decrease the incidence of late prosthetic valve endocarditis caused by viridans group streptococci.” [2]. Furthermore, the AHA emphasizes that the “maintenance of good oral health and regular access to dental care are considered more important to prevent viridans group streptococcal infective endocarditis than antibiotic prophylaxis for a dental procedure” [2].

Recent studies have shed more light on the complex association between oral health and cardiovascular disease. A growing body of evidence suggests that periodontal disease is closely associated with a higher risk of cardiovascular complications—including infective endocarditis (IE)—particularly in patients who undergo invasive dental procedures. A systematic review and meta-analysis by Kussainova et. al. reported that procedures like tooth extractions and oral surgery significantly raise the risk of IE in individuals already considered high-risk [3].

In addition, disruptions in the balance of oral microbiota have been linked to the development of valvular heart disease. Neculae et al. have detected oral bacteria in heart valve tissues and demonstrated that these microorganisms can travel to the heart, where they may initiate inflammatory and autoimmune reactions [4].

The value of preoperative dental screening is strongly supported by clinical guidelines and expert recommendations, which emphasize the need for close collaboration between dental and cardiology teams when preparing patients for cardiac surgery. Identifying and treating oral infections early needs to be performed in order to lower the risk of postoperative complications—such as prosthetic valve endocarditis—and to help improve overall surgical outcomes [5].

Despite these recommendations, the evidence supporting the necessity and optimal timing of dental interventions prior to heart valve surgery remains limited and, at times, conflicting. A systematic review conducted by Kouwenberg et al. found that the current evidence neither supports nor refutes the necessity of preoperative dental screening before heart valve surgery [6]. Lockhart et al. conducted a systematic review indicating that the existing evidence is unclear regarding the effect of dental treatment prior to heart valve surgery on postoperative outcomes, highlighting the necessity for additional research in this area [7]. Krasniqi et al. found no significant difference in the incidence of postoperative IE or prosthetic valve endocarditis between patients who underwent preoperative dental screening and those who did not [8]. On the other hand, a scoping review by Usmani et al. concluded that comprehensive dental care, including both preventive and therapeutic interventions, may be associated with a lower risk of cardiovascular events and mortality [9]. The data regarding the extent, types of procedures, and especially complications associated with dental evaluation in these patients are also limited. A systematic review conducted by Cotti et al. presented conflicting evidence regarding the timing and extent of dental treatment prior to heart valve surgery, ultimately concluding that “no satisfactory answers regarding dental care before cardiovascular invasive procedures are available” [10].

Given these considerations, the objective of this study was to assess the safety and feasibility of dental evaluation in patients undergoing heart valve replacement surgery at the Dental Clinic of the University Clinical Hospital Centre Zagreb.

2. Materials and Methods

A retrospective chart review was conducted on patients referred to the dental unit of the University Clinical Hospital Centre Zagreb for dental evaluation prior to heart valve surgery from 2021 to 2023.

Each patient underwent clinical examination and a panoramic x-ray. The dental evaluation consisted of the following: all patients with visible calculus deposits underwent supragingival instrumentation. Teeth with the following conditions were extracted: teeth with advanced caries that could not be restored, teeth with symptomatic radiolucency, teeth with asymptomatic radiolucency > 5 mm, teeth with advanced periodontal disease i.e., grade 3 mobility according to Miller’s classification [11] and/or symptoms, and symptomatic semi-impacted wisdom teeth. Extraction wounds were sutured according to the clinical judgment of the attending dentist. Bleeding was considered prolonged if hemostasis was not achieved within 30 min after the procedure. Delayed bleeding was defined as a bleeding occurring hours or days after the procedure.

Mild to moderate carious lesions (E1-D2 lesion according to the American Dental Association classification) were observed [12]. We performed caries removal and/or root canal treatment in symptomatic teeth that could have been restored. Antibiotic prophylaxis was administered according to the American Heart Association’s guidelines [3].

The following data were recorded: demographic information (age and sex), medical information (cardiological diagnosis and date of cardiosurgical procedure), and dental information (number of decayed, missing, and filled teeth (DMFT), number of symptomatic teeth, and number of teeth with periapical radiolucency). Additionally, we documented the number and type of dental procedures performed on each patient, including calculus removal, extractions, fillings, and endodontic treatments, along with any complications encountered (the type and treatment of the complication. The number of dental appointments and the time (i.e., number of days) required to obtain dental clearance for a heart valve procedure were also recorded.

Data was organized in table files (Microsoft Excel, Microsoft Inc., Redmond, WA, USA) and statistically processed in SPSS Version 21 (IBM Inc., Endicott, NJ, USA). The Kolmogorov–Smirnov test was used to assess the distribution of quantitative variables and determined that the variables were not normally distributed. Therefore, the median (min-max) was used to display continuous variables. Categorical variables were expressed as absolute numbers and proportions. To assess the difference between variables, the chi square test was used for categorical variables and Mann–Whitney or Kruskal–Wallis test was used for continuous variables. Values less than 0.05 (p < 0.05) were considered statistically significant.

3. Results

Overall, 153 patients (112 males and 41 females) underwent dental evaluation before heart valve surgery at the dental unit of the University Clinical Hospital Centre Zagreb in the study period (1 January 2021–31 December 2023).

The patients’ baseline characteristics are outlined in

Table 1. Baseline characteristics of patients.

			Difference by Sex (p)	Difference by Indication for Heart Valve Replacement (p)
Sex N (%)	Male	112 (73.2)	n.a.	0.006 §
	Female	41 (26.8)
Age median (range)		67 (19–87)	0.008 *	0.119
Diagnosis + N (%)	Aortic stenosis	80 (52.3)	0.060	n.a.
	Endocarditis	19 (12.4)
	Mitral insufficiency	30 (19.6)
	Mitral stenosis	4 (2.6)
	Aortic aneurysm	6 (3.9)
	Congenital heart defect	1 (0.7)
	Aortic insufficiency	11 (7.2)
	Tricuspid insufficiency	2 (1.3)
DMFT median (range)		22 (1–28)	0.158	0.294
Teeth with periapical radiolucency N (%)	Yes	32 (22.1)	0.784	0.973
	No	113 (77.9)
Number of teeth with periapical radiolucency per patient median (range)		0 (0–7)	0.9	0.978
Symptomatic teeth N (%)	Yes	2 (1.3)	0.456	<0.0001 §
	No	151 (98.7)
Number of symptomatic teeth per patient median (range)		0 (0–2)	0.451	<0.0001 §
Teeth for extraction N (%)	Yes	77 (50.3)	0.336	0.132
	No	76 (49.7)
Number of teeth for extraction per patient median (range)		1 (0–20)	0.505	0.153

⁺ indication for heart valve replacement. * p < 0.05 (Mann–Whitney test). ^§ p < 0.05 (Kruskal–Wallis test).

. The median age of the patients was 67 years. The most prevalent diagnosis was aortic stenosis, accounting for 80 cases (52.3%), followed by infective endocarditis, with 19 cases (12.4%). No significant differences in the distribution of various diagnoses between males and females were observed. A notable age disparity was identified between male and female patients, with males being significantly younger than females. No significant differences were observed in DMFT, the proportion of teeth with periapical radiolucency, the proportion of symptomatic teeth, and the number of teeth indicated for extraction between males and females, as well as among patients with varying diagnoses. A significant difference was observed in the proportion of symptomatic teeth and the median number of symptomatic teeth per patient among patients with varying diagnoses.

Table 2. Dental procedures performed in patients.

			Difference by Sex (p)	Difference by Indication for Heart Valve Replacement (p)
Tooth extraction N (%)	Yes	76 (49.7)	0.388	0.118
	No	77 (50.3)
Type of extraction N (%)	Routine	55 (72.4)	0.5578	0.675
	alveotomy	21 (27.6)
Scaling N (%)	Yes	29 (19)	0.079	0.714
	No	124 (81)
Caries removal N (%)	Yes	2 (1.3)	0.456	0.003 *
	No	151 (98.7)
Endodontics N (%)	Yes	7 (4.6)	0.604	0.510
	No	146 (95.4)
Antibiotic prophylaxis	Yes	18 (11.8)	0.029 *	<0.0001 *
	No	135 (88.2)
Type of antibiotic N (%)	Amoxicillin	12 (66.6)	n.a.	n.a.
	Azithromycin	1 (5.6)
	Clindamycin	1 (5.6)
	Doxycycline	2 (11.1)
	Cephalexine	2 (11.1)

* p < 0.05 (chi square test).

presents the dental procedures performed on patients. The predominant procedure was dental extraction, and this was conducted in 76 patients (49.7%). No significant difference was observed in the proportion of extractions among males and females and patients with varying diagnoses. A significant difference was observed in the amount of caries removal among patients with varying diagnoses. No significant differences were observed in other dental procedures among males and females and patients with varying diagnoses.

Antibiotic prophylaxis was administered in 18 (11.8%) patients. No significant difference in antibiotic prophylaxis administration was observed between males and females. Significant differences in antibiotic prophylaxis administration were observed between patients with different diagnosis. Patients with endocarditis received antibiotic prophylaxis significantly more (78.9% vs. 0–25%) than other diagnoses. The most common prophylactic antibiotic was amoxycillin (12/66.6%).

No significant difference in any of the observed variables was found between patients who underwent dental evaluation in a different year.

Complications were observed in 3 patients, representing 1.9% of the total cohort. Two patients (66.7%) experienced delayed bleeding and one (33.3%) had oroantral communication. The most common procedure after which the complications occurred was tooth extraction (2/66.7%), followed by supragingival instrumentation (1/33.3%). Delayed bleeding was controlled with local hemostatic measures (compression, tranexamic acid, resorbable sutures and hemostatic sponges). Oroantral communication was treated with resorbable hemostatic sponges, suturing, and antibiotics.

Table 3. Outcome of dental evaluation in patients undergoing heart valve replacement surgery.

			Difference by Sex (p)	Difference by Indication for Heart Valve Replacement (p)
Number of appointments needed to obtain dental clearance for cardiosurgical procedure N (%)	1	124 (81)	0.089	0.380
	2	20 (13.1)
	3	5 (3.3)
	4	4 (2.6)
Number of days needed to obtain dental clearance for cardiosurgical procedure median (range)	1 (1–45)		0.084	0.319
Patient outcome N (%)	Surgery performed	134 (87.6)	0.335	0.992
	Procedure postponed	15 (9.8)
	Lost to follow-up	4 (2.6)

presents the outcome of dental evaluation in our patients. In total, one to four appointments were required to achieve dental clearance for heart valve surgery, with 124 patients (81%) obtaining clearance in a single appointment. No significant differences were observed in the number of days or appointments required to obtain dental clearance for heart valve replacement procedure among males and females or among patients with different diagnoses.

Heart valve surgery was conducted in 134 patients (87.6%), whereas in 15 patients (9.8%) the procedure was deferred by the attending cardiologist or cardiac surgeon. Four patients, representing 2.6% of the cohort, were lost to follow-up. No significant differences were observed between males and females or among patients with varying diagnoses. No patient experienced a delay in their procedure as a result of complications arising from dental treatment. No significant difference was found in any of the observed variables between patients who underwent dental evaluation in a different year.

No patient experienced dental complications during the early postoperative period, specifically during the hospital admission for heart valve replacement surgery.

4. Discussion

To our knowledge, this is the first study to analyze safety and feasibility of dental evaluation before heart valve replacement surgery in the Croatian population. The predominant primary diagnosis among patients in this study was aortic stenosis. The findings align with the population-based study conducted by Iung et al., which analyzed patient data from 222 hospital centers across 28 European countries, revealing that aortic stenosis is the most prevalent form of valvular heart disease [13].

The data regarding the oral health of our patients, specifically a median DMFT index of 22 and a median of 1 tooth requiring extraction, suggests that their oral health is predominantly inadequate. The study by Radić et al. [14] reported a DMFT index of 12.5 for the general population aged 18–65 years in Croatia. The data indicate that patients undergoing heart valve surgery have poorer oral health than the general population. The findings align with those of Ghanbari et al., who identified the existence of a positive association between elevated DMFT and the prevalence of cardiovascular disease [15]. Conversely, Silvestre et al. observed no significant difference in the DMFT index between patients undergoing heart valve surgery and matched controls in terms of sex and age [16]. However, the same authors indicated a marked decline in periodontal health among these patients. This is in line with several major cohort studies that also confirmed the link between tooth loss, periodontal disease, and a greater risk of cardiovascular disease [17,18]. Despite the existing evidence linking poor oral health to cardiovascular diseases, additional research on this subject is necessary, as there are studies which argue whether this association is causal [19,20,21].

The predominant procedure conducted among our patients was tooth extraction, reinforcing our hypothesis regarding inadequate oral health and increased dental treatment requirements in this population. This result is in line with previous studies reporting that more than half of patients before heart valve surgery needed periodontal care or dental extractions [16,22]. Such a high rate of extractions underscores the importance of thorough dental screening due to the possible role of oral infection in the onset of IE [23]. The extraction of teeth affected by advanced caries, extensive periapical pathology, or severe periodontal disease follows current clinical recommendations [1,2]. These recommendations advocate for the removal of possible sources of infection prior to valve replacement surgery, even though the evidence about the impact of dental screening on postoperative IE (as well as other complications and patient survival) remains inconclusive [8,24,25].

Caries removal and/or root canal treatment was performed in patients who had advanced caries lesions (D3 according to the ADA scoring i.e., radiolucency extending to the inner third of the dentin) that were restorable or if the teeth were symptomatic but also restorable. If the caries destruction was too extensive, the teeth were extracted. Mild to moderate (E1-D2) caries lesions were observed due to following reasons: these patients were medically very complex and our intention was to optimize their oral health for a heart valve procedure without causing its delay. As we mentioned in the introduction, data regarding the extent and the type of procedures in these patients are limited. We thought that performing too many elective procedures would lead to delayed treatment, causing more harm than benefit to the patient. Performing all of these procedures would also create significant time and staffing requirements for our department. This approach is supported by the study of Rao et al., which found no difference in the early (<90 days) mortality and the frequency of reoperation due to infection in patients who underwent dental treatment limited to teeth with symptoms and/or evidence of active infection (fistula, suppuration) compared to patients who underwent comprehensive dental evaluation prior to heart valve replacement procedure [24].

At our department, antibiotic prophylaxis was administered to high-risk patients only, mainly the patients with IE before invasive dental procedures, which is in accordance with current AHA guidelines [2]. There were, however, patients who fell into moderate- or low-risk categories and were prescribed antibiotic prophylaxis by the attending cardiologist. This is probably due to the fact that compliance with current AHA guidelines on antibiotic prophylaxis is lower among cardiologists compared to dentists [26,27,28]. Antibiotic prophylaxis is effective in reducing the incidence of IE in high-risk patients, while it has no effect in terms of reducing the odds for developing IE in moderate- or low-risk patients [29].

Complications from dental treatment were observed in 3 patients, representing 1.9% of the total cases. No complications during dental treatment resulted in significant cardiovascular events or delays in heart valve replacement surgery. The low rates of intra- and postoperative complications indicate that the dental evaluation of patients undergoing heart valve surgery is a viable procedure with an acceptable risk profile. Comparable findings were documented in a study conducted by Casale et al. [30]. The authors observed no adverse outcomes associated with the dental procedure, including the postponement of cardiac procedures, heart failure, or mortality, despite the comparable postoperative results between patients who received preoperative oral care and those who did not. The findings contrast with those of a previous study conducted by Smith et al. in 2014, which examined morbidity and mortality linked to dental extraction prior to cardiac surgery [31]. This study found that 7% of patients experienced a definitive delay in their cardiac operation due to unforeseen complications arising from dental extraction, while 8% of patients encountered major adverse outcomes within 30 days of dental extraction prior to the cardiosurgical procedure [30]. In this study, 32% of patients underwent dental extractions under general anesthesia, potentially influencing certain complications and adverse outcomes noted.

Following dental evaluation, a significant majority of patients (87.6%) proceeded with their scheduled heart valve surgery. All surgeries proceeded as scheduled, unaffected by the dental evaluation and its associated complications. In this study, 153 patients were included, of which 124 patients (81%) achieved dental clearance for heart valve surgery following a single dental appointment. Additionally, no patients exhibited odontogenic pain or infection 30 days post-surgery, suggesting that this dental evaluation protocol can be executed with acceptable complication rates and within a reasonable timeframe, without necessitating the postponement of heart valve surgery. Rao et al. also reported that majority of their patients (73.1%) obtained dental clearance in one appointment [24].

This study presents several limitations that warrant consideration. First, it is a retrospective analysis subject to limitations such as missing or unrecorded data and convenience sampling. A control group (i.e., patients who did not receive dental interventions) was not established, as all patients at our institution are required to obtain dental clearance, with the sole exception being patients with life-threatening conditions necessitating urgent procedures. It is possible that some patients obtained dental clearance from their dentist without being referred to our clinic. Furthermore, the results present a single center experience, which reduces their generalizability to all patients.

In spite of the mentioned limitations, we believe that the results of this study are significant as they provide valuable data regarding dental procedures and their complications in patients awaiting heart valve surgery. Even though retrospective design limits conclusions about causality, it provides real-world clinical data which could be used for the development of new/updated protocols of dental evaluation in these patients.

5. Conclusions

While there is no consensus regarding the specific procedures and the scope of dental evaluation protocols for patients undergoing heart valve surgery, the findings of this study suggest that dental treatment in these patients demonstrates an acceptable safety profile and can be conducted within a reasonable timeframe without necessitating a delay in heart valve surgery.