European Journal of Cardiovascular Medicine

Laparoscopic cholecystectomy is among the most frequently performed abdominal operations, and safe progress depends on reliable identification of the cystic duct and cystic artery at the gallbladder neck. The region traditionally termed Calot’s triangle has long served as the key surgical landmark for this task, but its definition has evolved over time and the boundaries are described variably across surgical and anatomical texts [1]. Regardless of nomenclature, the hepatocystic region remains anatomically crowded, with the common hepatic duct, right hepatic artery, portal venous branches, lymphatics, and fibrofatty tissue converging within a confined space.

Bile duct injury and uncontrolled hemorrhage continue to be clinically relevant complications of cholecystectomy. Strategies that prioritize target identification, such as the Critical View of Safety, emphasize complete clearance of the hepatocystic triangle and confirmation that only two structures enter the gallbladder before division [2,3]. In parallel, a “safety zone” close to the gallbladder neck has been advocated to facilitate controlled exposure in the presence of ductal or vascular anomalies [9]. Cystic artery variants are a frequent source of disorientation because atypical origin, multiplicity, or an unusual course can mimic ductal structures and provoke bleeding that rapidly degrades the operative field.

Vascular consequences are not limited to intraoperative oozing; arterial injury can contribute to postoperative hemorrhage and, rarely, pseudoaneurysm formation involving the cystic artery or right hepatic artery [11]. Therefore, detailed knowledge of cystic artery morphology is not merely descriptive but forms part of practical risk reduction. Anatomical studies have shown that the cystic artery commonly arises from the right hepatic artery, but clinically important departures from this pattern are well documented across populations [4-6]. Contemporary syntheses further indicate that the artery is not consistently confined within the hepatobiliary triangle and can traverse anterior to the common hepatic duct or run inferior to, posterior to, or spirally around the cystic duct [5,8].

Early bifurcation, short arterial length, and multiple cystic arteries have additional procedural implications, particularly during clip placement and gallbladder bed dissection [4,5]. Variation in the cystic artery also reflects broader diversity in hepatic arterial anatomy. Cadaveric series demonstrate that accessory or aberrant right hepatic arteries and uncommon branching configurations are encountered with measurable frequency [12]. Complex combinations, including double cystic arteries arising from atypical sources, have been described and can alter the expected relationship between artery and duct [13,14]. Although imaging and intraoperative strategies reduce error, baseline population data from careful dissection remain essential for surgical education and anatomical orientation. Therefore, this study aimed (i) to determine the origin and number of cystic arteries, (ii) to describe their course in relation to Calot’s triangle and the cystic duct, and (iii) to characterize branching patterns and length parameters in adult cadavers.

Study design and setting

This cadaver-based observational study was carried out in the Department of Anatomy, RKDF Medical College and Hospital, Bhopal, Madhya Pradesh and Rohilkhand Medical College and Hospital, Bareilly, Uttar Pradesh, India (October 2016 to September 2024). Dissections were performed on embalmed adult cadavers used for routine undergraduate teaching. The work focused on descriptive documentation of cystic artery morphology and its topographic relationship to the hepatocystic region. Institutional permission for educational cadaver dissection and anonymized data recording was obtained from the department, and no donor identifiers were collected.

Study sample and eligibility

A total of 100 cadavers were included (N = 100). Cadavers with an intact hepatobiliary region and preserved porta hepatis anatomy were eligible. Specimens with gross disruption of the gallbladder fossa, severe postmortem damage, prior upper abdominal surgery evident on inspection, or distorted anatomy due to advanced decomposition were excluded. Each cadaver contributed one hepatobiliary specimen; bilateral assessment was not applicable.

Dissection procedure and operational definitions

After opening the abdominal cavity, the liver was elevated and the lesser omentum was reflected to expose the porta hepatis. The gallbladder, cystic duct, and common hepatic duct were identified, and fibrofatty tissue in the hepatocystic region was cleared using blunt and sharp dissection. For the purpose of this study, Calot’s triangle was interpreted in the contemporary hepatocystic sense, bounded by the cystic duct, common hepatic duct, and inferior surface of the liver, while noting that historical descriptions differ [1]. The cystic artery was defined as the principal artery (or arteries) supplying the gallbladder and was traced from the gallbladder neck toward its source vessel. Any additional arteries entering the gallbladder independently were recorded as accessory cystic arteries.

Variables and measurements

The following variables were recorded: (i) origin of the cystic artery (right hepatic artery, hepatic artery proper, left hepatic artery, gastroduodenal artery, or aberrant right hepatic artery); (ii) number of cystic arteries (single/double/triple); (iii) course with respect to Calot’s triangle (within the triangle, anterior to the common hepatic duct, or partly posterior to the cystic duct outside the triangle); and (iv) relation to the cystic duct (anterior, posterior, or spiral/encircling). Branching characteristics were categorized as early bifurcation (division before reaching the gallbladder) or division near the gallbladder wall, and “surgically important” short arteries were defined as <10 mm in length based on prior anatomical descriptions [5,8]. Arterial length was measured from the point of origin to the first major bifurcation using a calibrated metric scale placed along the vessel course; measurements were recorded to the nearest millimeter.

Statistical analysis

Data were entered in a structured proforma and checked for completeness. Categorical variables are presented as frequency and percentage. Continuous data (arterial length) are summarized as mean ± standard deviation and range. Because the objectives were descriptive, no hypothesis testing was performed.

A total of 100 adult cadavers were examined. In all specimens, the cystic artery (or arteries) supplying the gallbladder could be identified and traced to its source vessel.

Origin of the cystic artery showed a clear predominance of the right hepatic artery. The cystic artery arose from the right hepatic artery in 82% of specimens. Less common origins included the hepatic artery proper (7%), left hepatic artery (4%), gastroduodenal artery (3%), and an aberrant right hepatic artery (4%) (Table 1).

Table 1. Origin of the cystic artery (N = 100)

Regarding multiplicity, a single cystic artery was present in 88% of cadavers, while double arteries were identified in 10% and triple arteries in 2% (Table 2).

Table 2. Number of cystic arteries identified (N = 100)

With respect to its topographic course, the cystic artery lay within Calot’s triangle in 76% of cases. An anterior course to the common hepatic duct was observed in 18%, and in 6% the artery ran partly posterior to the cystic duct outside the triangle (Table 3).

Table 3. Course of cystic artery in relation to Calot’s triangle (N = 100)

The relationship of the cystic artery to the cystic duct varied: 64% coursed posterior to the cystic duct, 22% anterior to it, and 14% followed a spiral/encircling pattern (Table 4). Early bifurcation before reaching the gallbladder was noted in 21%, while 79% divided near the gallbladder wall. Short cystic arteries (<10 mm) were documented in 9%, and a tortuous artery running close to the common hepatic duct–cystic duct junction was seen in 11% (Table 4). The mean cystic artery length was 18.6 ± 4.2 mm, with values ranging from 10 mm to 32 mm (Table 4).

Table 4. Relation of cystic artery to cystic duct and branching/length characteristics (N = 100)

This cadaver-based series demonstrates that the classical pattern of a single cystic artery arising from the right hepatic artery remains the predominant configuration, but clinically relevant departures from this pattern are frequent enough to warrant routine anticipation during dissection. In the present study, 82% of cystic arteries originated from the right hepatic artery, a proportion comparable with large anatomical syntheses that identify the right hepatic artery as the principal source [5,8]. Population studies have shown similar distributions, with Chen and colleagues reporting right hepatic origin as the most common pattern in their autopsy series [6].

Atypical origins in this study included the hepatic artery proper, left hepatic artery, gastroduodenal artery, and aberrant right hepatic artery. Such diversity is important because an aberrant right hepatic artery can traverse the hepatocystic region and shift the expected position of the cystic artery relative to the common hepatic duct [12]. Although uncommon, complex arterial constellations involving accessory hepatic arteries and multiple cystic arteries have been described, emphasizing the embryological and surgical relevance of variant supply pathways [13,14].

Multiplicity was observed in 12% of cadavers (double 10%, triple 2%). This frequency aligns with the broader literature, in which double cystic arteries are consistently documented, even if exact rates vary with definitions and dissection technique [5,8]. From a procedural perspective, multiplicity can explain persistent bleeding after presumed control of the cystic artery and can lead to inadvertent clipping of a non-target vessel if the operative field is obscured [4,5].

Topographically, 76% of arteries coursed within Calot’s triangle, while 18% ran anterior to the common hepatic duct. An anterior relationship to the common hepatic duct is a recognized high-attention pattern because traction, cautery, or blind clipping can jeopardize the duct or adjacent arterial branches. Torres et al. demonstrated that the course of the cystic artery varies during laparoscopic exposure, reinforcing the value of deliberate tissue clearance and direct visualization rather than reliance on an “infundibular” impression [7]. Similarly, the present distribution of posterior (64%), anterior (22%), and spiral (14%) courses relative to the cystic duct matches the heterogeneous patterns summarized in recent meta-analysis [8].

Early bifurcation (21%) and short arteries (9%) are surgically significant because they reduce the available length for secure clip placement and increase the chance that a clip is applied after division, leading to hemorrhage from a gallbladder wall branch. Our mean length (18.6 mm) is close to pooled estimates reported in comprehensive reviews [8]. These findings support contemporary safety frameworks: the Critical View of Safety requires full exposure of the cystic plate and clear demonstration of the two structures entering the gallbladder before any division [2,3]. Photo documentation of an achieved critical view has been associated with evaluation of ductal safety and provides a practical audit tool in routine practice [10]. Finally, awareness of cystic artery proximity and branching is relevant not only intraoperatively but also for rare delayed vascular complications such as pseudoaneurysm after laparoscopic cholecystectomy [11].

Limitations

This study relied on embalmed cadavers, and formalin fixation affects vessel pliability and can alter measured length. Demographic variables such as age and sex were not available for all donors, preventing subgroup comparisons. Vascular injection techniques were not used, so very small accessory arterial twigs were underrepresented. The work was descriptive and did not link anatomical patterns with operative outcomes or bleeding rates.

In this cadaver-based study of 100 specimens, the cystic artery most commonly originated from the right hepatic artery and was single, with most vessels coursing within Calot’s triangle. Nonetheless, atypical origins from the hepatic artery proper, left hepatic artery, gastroduodenal artery, and aberrant right hepatic artery were documented, along with multiple cystic arteries in 12% of cases. A substantial subset showed an anterior course to the common hepatic duct or a spiral relationship to the cystic duct, and early bifurcation and short arterial length were observed. These variations emphasize careful clearance of the hepatocystic region, secure identification of ductal and arterial structures, and routine adherence to safety principles during cholecystectomy.

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