diff --git a/lib/connection.js b/lib/connection.js
index 0b3ec6ae0e..eea265260d 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -111,6 +111,9 @@ Object.defineProperty(Connection.prototype, 'readyState', {
     if (
       this._readyState === STATES.connected &&
       this._lastHeartbeatAt != null &&
+      // LoadBalanced topology (behind haproxy, including Atlas serverless instances) don't use heartbeats,
+      // so we can't use this check in that case.
+      this.client?.topology?.s?.description?.type !== 'LoadBalanced' &&
       typeof this.client?.topology?.s?.description?.heartbeatFrequencyMS === 'number' &&
       Date.now() - this._lastHeartbeatAt >= this.client.topology.s.description.heartbeatFrequencyMS * 2) {
       return STATES.disconnected;
diff --git a/lib/drivers/node-mongodb-native/connection.js b/lib/drivers/node-mongodb-native/connection.js
index 641703e4b1..a17fc64131 100644
--- a/lib/drivers/node-mongodb-native/connection.js
+++ b/lib/drivers/node-mongodb-native/connection.js
@@ -426,9 +426,6 @@ function _setClient(conn, client, options, dbName) {
   }
 
   conn.onOpen();
-  if (client.topology?.s?.state === 'connected') {
-    conn._lastHeartbeatAt = Date.now();
-  }
 
   for (const i in conn.collections) {
     if (utils.object.hasOwnProperty(conn.collections, i)) {